duramax diesel engine (lml/lgh) - 2011 black plate (1,1 ... · duramax diesel engine (lml/lgh) ......

Black plate (1,1)DURAMAX Diesel Engine (LML/LGH) - 2011

2011 DURAMAX Diesel Engine (LML/LGH) M

In Brief . . . . . . . . . . . . . . . . . . . . . . . . 1-1Initial Drive Information . . . . . . . . 1-1Performance andMaintenance . . . . . . . . . . . . . . . . . 1-2

Instruments and Controls . . . . 5-1Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . 5-2

Information Displays . . . . . . . . . . 5-10Vehicle Messages . . . . . . . . . . . . 5-11Vehicle Personalization . . . . . . . 5-15

Driving and Operating . . . . . . . . 9-1Starting and Operating . . . . . . . . . 9-1Engine Exhaust . . . . . . . . . . . . . . 9-10Brakes . . . . . . . . . . . . . . . . . . . . . . . 9-16Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 9-17Towing . . . . . . . . . . . . . . . . . . . . . . . 9-37Conversions andAdd-Ons . . . . . . . . . . . . . . . . . . . . 9-42

Vehicle Care . . . . . . . . . . . . . . . . . 10-1General Information . . . . . . . . . . 10-2Vehicle Checks . . . . . . . . . . . . . . . 10-4Electrical System . . . . . . . . . . . . 10-29

Service and Maintenance . . . 11-1General Information . . . . . . . . . . 11-1Scheduled Maintenance . . . . . . 11-2Recommended Fluids,Lubricants, and Parts . . . . . . . 11-8

Maintenance Records . . . . . . . 11-12

Technical Data . . . . . . . . . . . . . . . 12-1Vehicle Data . . . . . . . . . . . . . . . . . . 12-2

Index . . . . . . . . . . . . . . . . . . . . . i-1


ii Introduction

The names, logos, emblems,slogans, vehicle model names, andvehicle body designs appearing inthis manual including, but not limitedto, GM, the GM logo, CHEVROLET,GMC, the CHEVROLET and GMCTruck Emblems, SILVERADO,SIERRA, DENALI, EXPRESS,SAVANA, and Duramax aretrademarks and/or service marksof General Motors LLC, itssubsidiaries, affiliates, or licensors.

This manual describes features thatmay or may not be on your specificvehicle either because they areoptions that you did not purchase ordue to changes subsequent to theprinting of this owner manual.

Please refer to the purchasedocumentation relating to yourspecific vehicle to confirm each ofthe features found on your vehicle.For vehicles first sold in Canada,substitute the name “GeneralMotors of Canada Limited” for GMCand Chevrolet Motor Divisionwherever it appears in this manual.

This manual contains informationthat pertains to the operation of yourdiesel engine. It also contains yourDiesel Maintenance Schedule.The sections in this manualcorrespond to the sections in yourowner manual. This manual, alongwith your owner manual, will assistyou in the proper use andmaintenance of your vehicle.

Keep this manual in the vehicle forquick reference.

Canadian Vehicle Owners

Propriétaires Canadiens

A French language copy of thismanual can be obtained from yourdealer or from:

On peut obtenir un exemplaire dece guide en français auprès duconcessionnaire ou à l'adressesuivante:

Helm, IncorporatedP.O. Box 07130Detroit, MI 48207

1-800-551-4123Numéro de poste 6438 delangue françaisewww.helminc.com

Litho in U.S.A.Part No. 22743552 A First Printing ©2010 General Motors LLC. All Rights Reserved.


Introduction iii

Using this SupplementThis supplement containsinformation specific to the uniquecomponents of the vehicle. It doesnot explain everything you need toknow about the vehicle. Read thissupplement along with the ownermanual to learn about the vehicle'sfeatures and controls.

Index

A good place to look for what youneed is the Index in back of thissupplement. It is an alphabetical listof what is in the supplement, andthe page number where you willfind it.


iv Introduction

2 NOTES


In Brief 1-1

In Brief

Initial Drive InformationTransmission . . . . . . . . . . . . . . . . . . 1-1

Performance andMaintenanceEngine Oil Life System . . . . . . . . 1-2Diesel Particulate Filter(Exhaust Filter) . . . . . . . . . . . . . . 1-3

Diesel Exhaust Fluid . . . . . . . . . . 1-5

Initial DriveInformation

TransmissionCold Operation(Allison Transmission)

When temperatures are very cold,the transmission will prevent certainoperations to protect againstdamage. The chart below showsshift range availability based ontransmission oil temperature:. All shift ranges available at

−25 C (−13 F) or above.. 2 (Second) and 3 (Third) shift

ranges only at −35 C (−31 F) to−25 C (−13 F).

. 2 (Second) shift range only at−35 C (−31 F) or lower.

Torque converter clutch operationwill also be prevented when air ortransmission oil temperatures arebelow certain levels.

For areas where ambienttemperatures are below−40 C (−40 F), use synthetictransmission fluid approved toAllison Transmission specificationTES‐295. See RecommendedFluids and Lubricants on page 11‑8and Automatic Transmission Fluidon page 10‑11.

Adaptive Shift Controls

The shift quality of a new vehiclemay not be ideal because theAdaptive Shift Control process maynot have determined the bestsettings for a particular shift orcondition. Shift quality will improvewith continued driving.

Low Traction Mode(Allison Transmission)

Low Traction Mode aids in vehicleacceleration on slippery roadsurfaces such as ice or snow.By selecting 2 (Second) usingRange Selection Mode while at astop, the transmission will limittorque to the drive wheels toprevent slippage.


1-2 In Brief

Heater Performance Mode(Allison Transmission)

When cold weather conditions aredetected, the transmission raisespart throttle upshift points afterthe 1 (First) to 2 (Second) upshiftto increase engine speed.This feature shortens engine andcab warm up times.

When the transmission is in thismode, upshifts may be delayed.This is normal and does notindicate an operational problem.

Four Wheel Drive(Allison Transmission)

When operating in 4↓(Four-Wheel-Drive Low), thereis a very deep gear reduction.The resulting shifts will feelexaggerated.

Performance andMaintenance

Engine Oil Life SystemThe engine oil life system calculatesengine oil life based on vehicle useand, on most vehicles, displays aDIC message when it is necessaryto change the engine oil and filter.The oil life system should be resetonly following an oil change.

Resetting the Oil Life System

To reset the Engine Oil Life Systemon van models:

1. Display the OIL LIFEREMAINING on the DIC.

2. Press and hold the SET/RESETbutton on the DIC for more thanfive seconds. The oil life willchange to 100%.

To reset the Engine Oil Life Systemon most pickup models:

1. Display the OIL LIFEREMAINING on the DIC. If thevehicle does not have DICbuttons, the vehicle must be inP (Park) to access this display.

2. Press and hold the SET/RESETbutton on the DIC, or the tripodometer reset stem if thevehicle does not have DICbuttons, for more thanfive seconds. The oil life willchange to 100%.


In Brief 1-3

On all models, the Engine Oil LifeSystem can be reset as follows:

1. Turn the ignition to ON/RUN withthe engine off

2. Fully press the accelerator pedalslowly three times withinfive seconds.

3. Display the OIL LIFEREMAINING on the DIC. If thedisplay shows 100%, the systemis reset.

4. Turn the key to LOCK/OFF.

See Engine Oil Life System onpage 10‑10.

Diesel Particulate Filter(Exhaust Filter)The Duramax engine is equippedwith a Diesel Particulate Filter (DPF)that, by design, will filter or trapparticulates. The DPF is locatedunder the vehicle in the exhaustsystem and looks like a catalyst.

Depending on a number of factorsmonitored by the engine computer,the DPF will need to be cleaned ofaccumulated solids. When acleaning is needed, the enginecomputer will initiate a cleaningaction by warming the exhaust gastemperature. This feature has beendesigned to operate automatically,with limited operator involvement orawareness.

Cleaning the DPF(Exhaust Filter)

While the DPF cleaning isautomatically controlled by theengine computer, the vehicle willneed to operate continuously forapproximately 30 minutes and atspeeds greater than 48 km/h(30 mph) to clean the DPFeffectively. If the vehicle is returnedto idle during the cleaning process,the driver may notice a slightlydifferent sound or a slightly elevatedengine idle speed. This is normal.No action is required on the part ofthe driver during a regular DPFcleaning. See Diesel ParticulateFilter (Exhaust Filter) on page 9‑10.


1-4 In Brief

Special DPF Driver Messages

If the vehicle is used for numerousshort trips or extended slow-speedoperation, the engine computer maynot be able to adequately heat upthe exhaust system to clean theDPF effectively. The enginecomputer has been designed tocontinuously monitor the conditionof the DPF. When the enginecomputer detects that the DPF isnearly full of particulates and thatthe vehicle is not being operated ina manner that would allow effectiveautomatic DPF cleaning, the DriverInformation Center will display themessage CLEANING EXHAUSTFILTER KEEP DRIVING UNTILMESSAGE IS CLEARED.

If the vehicle continues to bedriven in a manner that preventseffective DPF cleaning, the DPF willbecome plugged with particulates.

If this occurs, the engine computerwill turn on the Service Engine SoonLight in the instrument cluster andthe DIC will display the messageREDUCED ENGINE POWER.See Diesel Particulate Filter(Exhaust Filter) on page 9‑10and Engine Power Messages onpage 5‑11.

Fuel

Use Ultra-Low Sulfur DieselFuel (ULSD)

Use Ultra-Low Sulfur Diesel Fuel(ULSD) only. The emission controlhardware used on the vehicle maybe damaged by using fuel with highsulfur levels. Use only fuel that isdispensed from pumps bearing theULSD label.

Do Not Use Low Sulfur DieselFuel (LSD)

Do not use fuel that is dispensedfrom pumps bearing the LSD label.

Do Not Use Non-Highway Fuel

Fuel labeled as off road ornon-highway is typically veryhigh in sulfur content and willdamage the emission controlsystem. Non-Highway fuel is notintended for use in on-highwayvehicles and does not have thefuel properties needed by theDPF-equipped Duramax Diesel.

In addition:. Use the correct engine oil.. Do not add gasoline to

diesel fuel.. Do not modify the induction or

exhaust systems.

See Fuel for Diesel Engines onpage 9‑17 and Engine Oil onpage 10‑7.


In Brief 1-5

Diesel Exhaust FluidDiesel Exhaust Fluid (DEF) is usedwith diesel engines to reduce theamount of regulated emissionsproduced. The DEF system must bemaintained for the vehicle to runproperly.

Locating Diesel Exhaust Fluid

DEF can be purchased at aChevrolet or GMC dealer. It canalso be purchased at authorizedvehicle and truck dealerships.Additionally, some diesel truckfuelling stations or retailers mayalso have DEF for purchase. Forvehicles with an active OnStar®

subscription, OnStar can help tolocate a DEF retailer. For moreinformation on locating DEF seewww.afdc.energy.gov/afdc/vehicles/diesels_fluid.html. See “CustomerAssistance Offices” in the ownermanual for phone numbers to assistyou in contacting a GM dealer.See Recommended Fluids andLubricants on page 11‑8.

As the DEF tank becomes lowon fluid, warnings begin withapproximately 1600 km (1000 miles)of remaining range. These warningswill increase in intensity as the tankbecomes empty. Once the tank isempty, the vehicle will be speedlimited to 89 km/h (55 mph) andeventually to 7km/h (4 mph).The tank should be refilled toavoid vehicle speed limitation.If there is an issue with the qualityof the fluid or the exhaust fluidsystem, warnings will be displayedin the Driver Information Center(DIC). The vehicle will have 322 km(200 miles) before being speedlimited to 89 km/h (55 mph). If thevehicle continues to be driven in thiscondition, it will become speedlimited to 7km/h (4 mph). See DieselExhaust Fluid on page 9‑12.


1-6 In Brief

2 NOTES


Instruments and Controls 5-1

Instruments andControls

Warning Lights, Gauges, andIndicatorsInstrument Cluster . . . . . . . . . . . . 5-2Fuel Gauge . . . . . . . . . . . . . . . . . . . 5-4Engine Oil Pressure Gauge . . . 5-5Malfunction Indicator Lamp . . . 5-6Wait-to-Start Light . . . . . . . . . . . . . 5-9Diesel Exhaust Fluid (DEF)Warning Light . . . . . . . . . . . . . . . . 5-9

Information DisplaysDriver InformationCenter (DIC) . . . . . . . . . . . . . . . 5-10

Vehicle MessagesVehicle Messages . . . . . . . . . . . 5-11Engine Cooling SystemMessages . . . . . . . . . . . . . . . . . . 5-11

Engine Oil Messages . . . . . . . . 5-11Engine Power Messages . . . . 5-11Fuel System Messages . . . . . . 5-12Diesel Exhaust FluidMessages . . . . . . . . . . . . . . . . . . 5-12

Diesel Particulate FilterMessages . . . . . . . . . . . . . . . . . . 5-12

Service Vehicle Messages . . . 5-13Starting the VehicleMessages . . . . . . . . . . . . . . . . . . 5-13

Transmission Messages . . . . . 5-14Vehicle Speed Messages . . . . 5-14

Vehicle PersonalizationVehicle Personalization . . . . . . 5-15


5-2 Instruments and Controls

Warning Lights, Gauges, and Indicators

Instrument Cluster

English Pickup Shown, Metric Similar



English Van Shown, Metric Similar



See the owner manual fortelltales and gauges not listed insupplement.

Fuel Gauge

Metric Pickup Models

English Pickup Models

Metric Van Models

English Van Models

When the ignition is on, the fuelgauge shows approximately howmuch fuel the vehicle has left in thetank. The gauge will first indicateE (empty) before the vehicle is outof fuel, but the vehicle's fuel tankshould be filled soon.

An arrow on the fuel gaugeindicates the side of the vehiclethe fuel door is on.



Listed are four situations customersmay experience with the fuel gauge:. At the gas station, the fuel pump

shuts off before the gauge readsF (full).

. It takes a little more or less fuelto fill up than the fuel gaugeindicated. For example, thegauge may have indicated thetank was half full, but it actuallytook a little more or less thanhalf the tank's capacity to fillthe tank.

. The gauge moves a little whileturning a corner or speeding up.

. The gauge does not go back toE (empty) when the ignition isturned off.

None of these indicate a problemwith the fuel gauge.

For information on how to fill thefuel tank, see Filling the Tank onpage 9‑35.

The vehicle also has a fuel cooler.To clean, powerwash the bottom ofthe vehicle.

Engine Oil PressureGauge

Metric Pickup Models

English Pickup Models

Metric Van Models



English Van Models

{ WARNING

Do not keep driving if the oilpressure is low. The engine canbecome so hot that it catches fire.Someone could be burned. Checkthe oil as soon as possible andhave the vehicle serviced.

Notice: Lack of proper engine oilmaintenance can damage theengine. The repairs would not becovered by the vehicle warranty.Always follow the maintenanceschedule for changing engine oil.

The engine oil pressure gaugereads in kPa (kilopascals) or psi(pounds per square inch) when theengine is running. Oil pressure mayvary with engine speed, outsidetemperature and oil viscosity.

If readings are outside the normaloperating range, the low oilpressure message may display onthe Driver Information Center (DIC),or for vehicles without DIC the oilpressure light comes on. If the oillevel is outside the normal operatingrange of 0-548 kPa (0-80 psi), checkthe oil level immediately. DO NOToperate the engine with the oilpressure warning light on or aENGINE OIL LOW ADD OILmessage displayed.

MalfunctionIndicator LampA computer system called OBD II(On-Board Diagnostics-SecondGeneration) monitors operation ofthe fuel, ignition, and emissioncontrol systems. It makes sure thatemissions are at acceptable levelsfor the life of the vehicle, helping toproduce a cleaner environment.

This light comes on when theignition is on, but the engine is notrunning, as a check to show it isworking. If it does not, have thevehicle serviced by your dealer.



If the check engine light comes onand stays on, while the engine isrunning, this indicates that there isan OBD II problem and service isrequired.

This light also comes on when theDiesel Exhaust Fluid (DEF) is notworking. See Diesel Exhaust Fluidon page 9‑12 for more information.

Malfunctions often are indicated bythe system before any problem isapparent. Heeding the light canprevent more serious damage to thevehicle. This system assists theservice technician in correctlydiagnosing any malfunction.

Notice: If the vehicle iscontinually driven with this lighton, after a while, the emissioncontrols might not work as well,the vehicle fuel economy mightnot be as good, and the enginemight not run as smoothly.This could lead to costly repairsthat might not be covered by thevehicle warranty.

Notice: Modifications made to theengine, transmission, exhaust,intake, or fuel system of thevehicle or the replacement ofthe original tires with otherthan those of the same TirePerformance Criteria (TPC) canaffect the vehicle's emissioncontrols and can cause this lightto come on. Modifications tothese systems could lead tocostly repairs not covered bythe vehicle warranty. This couldalso result in a failure topass a required EmissionInspection/Maintenance test.See Accessories andModifications on page 10‑2.

This light comes on during amalfunction in one of two ways:

Light Flashing: A misfire conditionhas been detected. A misfireincreases vehicle emissions andcould damage the emission controlsystem on the vehicle. Diagnosisand service might be required.

The following can prevent moreserious damage to the vehicle:. Reduce vehicle speed.. Avoid hard accelerations.. Avoid steep uphill grades.. If towing a trailer, reduce the

amount of cargo being hauled assoon as it is possible.

If the light continues to flash, whenit is safe to do so, stop the vehicle.Find a safe place to park thevehicle. Turn the vehicle off, wait atleast 10 seconds, and restart theengine. If the light is still flashing,follow the previous steps and seeyour dealer for service as soon aspossible.



Light On Steady: An emissioncontrol system malfunction hasbeen detected on the vehicle.Diagnosis and service might berequired.

An emission system malfunctionmight be corrected by doing thefollowing:. If the vehicle has been driven

through a deep puddle of water,the vehicle's electrical systemmight be wet. The condition isusually corrected when theelectrical system dries out.A few driving trips should turnthe light off.

. Make sure to fuel the vehiclewith quality fuel. Poor fuel qualitycauses the engine not to run asefficiently as designed and maycause: stalling after start-up,

stalling when the vehicle ischanged into gear, misfiring,hesitation on acceleration,or stumbling on acceleration.These conditions might go awayonce the engine is warmed up.

If one or more of theseconditions occurs, change thefuel brand used. It will require atleast one full tank of the properfuel to turn the light off.

See Fuel for Diesel Engines onpage 9‑17.

If none of the above have made thelight turn off, your dealer can checkthe vehicle. The dealer has theproper test equipment anddiagnostic tools to fix anymechanical or electrical problemsthat might have developed.

Emissions Inspection andMaintenance Programs

Some state/provincial andlocal governments may haveprograms to inspect the on-vehicleemission control equipmentFor the inspection, the emissionsystem test equipment isconnected to the vehicle’sData Link Connector (DLC).

The DLC is under the instrumentpanel to the left of the steeringwheel. See your dealer if assistanceis needed.



The vehicle may not passinspection if:. the check engine light is on with

the engine running, or if the lightdoes not come on when theignition is turned to ON/RUNwhile the engine is off.

. the critical emission controlsystems have not beencompletely diagnosed by thesystem. This can happen if thebattery has recently beenreplaced or if the battery hasrun down. The diagnosticsystem evaluates criticalemission control systems duringnormal driving. This can takeseveral days of routine driving.If this has been done and thevehicle still does not pass theinspection , your dealer canprepare the vehicle forinspection.

Wait-to-Start Light

The wait to start light shows that theengine is functioning properly andindicates when the engine can bestarted.

The fast warm-up glow plug systemmakes the wait to start light stay onfor a shorter amount of time thanmost diesel engines.

For more information, see Startingthe Diesel Engine on page 9‑1.

Diesel Exhaust Fluid(DEF) Warning Light

This light, a Driver InformationCenter (DIC) Message, and a chimecome on when there is an issue withthe Diesel Exhaust Fluid.

See Diesel Exhaust Fluid Messageson page 5‑12 for information on thespecific message displaying with thelight.

If the DEF fluid level has not beencorrected, the light will continue toflash when the vehicle is started orafter a fuel refill. The vehicle'sspeed may also be limited.

Also see Diesel Exhaust Fluid onpage 9‑12 for more information.



Information Displays

Driver InformationCenter (DIC)The Driver Information Center (DIC)is located on the instrument panelabove the steering wheel. The DICcomes on when the ignition is on.

A Duramax Diesel vehicle may havethe following additional DIC menuitems.

FUEL FILTER LIFE REMAINING

To access this display, the vehiclemust be in P (Park). If your vehiclehas DIC buttons, press the vehicleinformation button until FUELFILTER LIFE REMAINING displays.

If your vehicle does not have DICbuttons, press the trip stem untilFUEL FILTER LIFE REMAININGdisplays. This display shows anestimate of the fuel filter's remaininguseful life. If you see 90% FUELFILTER LIFE REMAINING on thedisplay, it means 90% of the currentfuel filter life remains. The fuel filterlife system will alert you to changeyour fuel filter on a scheduleconsistent with your drivingconditions.

When the remaining fuel filter life islow, the CHANGE FUEL FILTERmessage will appear on the display.You should change your fuel filter assoon as you can.

FUEL FILTER LIFE RESET

You must reset the FUEL FILTERLIFE REMAINING display after eachfuel filter change. It will not resetitself. Also, be careful not to resetthe FUEL FILTER LIFE REMAININGdisplay at any time other thanwhen the fuel filter has just beenchanged because it cannot be resetaccurately until the next fuel filterchange. The fuel filter life willchange to 100% when the systemhas been reset. To reset the system,press and hold the set/reset button,or the trip stem if there are no DICbuttons, for two seconds whileFUEL FILTER LIFE REMAINING isdisplayed on the DIC.



Vehicle MessagesThe Driver Information Center (DIC)will display warning messages if aproblem is detected. Pressing theselect button or the set/reset buttonfor vehicle with DIC buttons, or thetrip odometer reset stem forvehicles without DIC buttons,will acknowledge some currentwarning or service messages.Other messages are more urgentand cannot be cleared from thedisplay until the issue is corrected.

The following are some additionalmessages that the Duramax Dieselvehicle can display.

Engine Cooling SystemMessages

COOLANT LEVEL LOWADD COOLANT

Notice: Engine damage fromrunning your engine withoutcoolant is not covered by yourwarranty. See “OverheatedEngine Protection OperatingMode” in the Index of yourowner's manual for informationon driving to a safe place in anemergency.

If your vehicle has a low coolantlevel sensor, this message willappear on the DIC if the enginecoolant level is low. Adding coolantto the coolant recovery tank willclear the message. See “EngineCoolant” in the owner manual.

Engine Oil Messages

ENGINE OIL LOW ADD OIL

If your vehicle has an oil levelsensor, this message displaysif the oil level in the vehicle is low.Check the oil level and correct it asnecessary. You may need to let thevehicle cool or warm up and cyclethe ignition to be sure this messageclears.

This message clears itself after10 seconds, until the next ignitioncycle. See Engine Oil on page 10‑7for additional information.

Engine Power Messages

ENGINE POWER IS REDUCED

A computer monitors the operationof the electric accelerator. If theENGINE POWER IS REDUCEDmessage comes on while driving,there will be a reduction inperformance and acceleration.You should take the vehicle infor service.



Fuel System Messages

CHANGE FUEL FILTER

This message will appear on theDIC for 10 seconds when a fuel filterchange is required. See Fuel FilterReplacement on page 9‑33 for moreinformation.

WATER IN FUEL SERVICEREQUIRED

This message will come on to warnyou if there is water in the dieselfuel system. For more informationon how this message works, seeWater in Fuel on page 9‑27.

Diesel Exhaust FluidMessages

EXHAUST FLUID EMPTYREFILL NOW

This message will be displayedwhen the exhaust fluid is empty.This message may be accompaniedby other messages that providemore information.

EXHAUST FLUID LOW SPEEDLIMITED SOON

When the exhaust fluid range is lessthan 120 km (75 miles) this messagewill be displayed.

EXHAUST FLUID RANGE: XXX

When the exhaust fluid is gettinglow, the range will be displayed ineither kilometers or miles. It isnormal for the EXHAUST FLUIDRANGE to vary based on vehicleand environmental drivingconditions.

EXHAUST FLUID QUALITYPOOR SEE OWNERSMANUAL NOW

This message displays when theexhaust fluid is of poor quality.This message may be accompaniedby other messages that providemore information.

Diesel Particulate FilterMessages

CLEANING EXHAUST FILTERKEEP DRIVING UNTILMESSAGE IS CLEARED

This message will appear on theDIC when an exhaust particulatefilter cleaning is required. To cleanthe filter, drive the vehicle above50 km/h (30 mph) until the warningmessage goes off. This will takeabout 30 minutes.

If the filter is not cleaned, themalfunction indicator lamp will comeon and the REDUCED ENGINEPOWER message will be displayed.Vehicle performance will be limited.See Diesel Particulate Filter(Exhaust Filter) on page 9‑10 formore information.



Service Vehicle Messages

SERVICE EXHAUST FLUIDSYSTEM SEE OWNERSMANUAL NOW

This message displays when theexhaust fluid system needs service.This message may be accompaniedby other messages that providemore information.

Starting the VehicleMessages

ELEVATED IDLE OFF

If your vehicle does not have DICbuttons, this message will appearwhen the elevated idle/exhaustrestrictor feature has been turnedoff. This feature can be turned onor off by pressing the pedals.For more information on theelevated idle/exhaust restrictorfeature, see “Elevated Idle” underStarting the Diesel Engine onpage 9‑1.

If your vehicle has DIC buttons, thismessage will not be displayed.The Elevated Idle can be turned onor off using the customizationmenus. Press the customizationbutton until ELEVATED IDLEappears on the DIC display. Pressthe set/reset button once to accessthe settings for this feature. Thenpress the customization button toscroll through the following settings:OFF, ON or NO CHANGE. Chooseone of the available settings andpress the set/reset button while it isdisplayed on the DIC to select it.

ELEVATED IDLE ON

If your vehicle does not have DICbuttons, this message will appearwhen the elevated idle/exhaustrestrictor feature has been turnedon. This feature can be turned onor off by pressing the pedals.

For more information on theelevated idle/exhaust restrictorfeature, see “Elevated Idle” underStarting the Diesel Engine onpage 9‑1.

If your vehicle has DIC buttons,this message will not be displayed.The Elevated Idle can be turned onor off using the customizationmenus. Press the customizationbutton until ELEVATED IDLEappears on the DIC display. Pressthe set/reset button once to accessthe settings for this feature. Thenpress the customization button toscroll through the following settings:OFF, ON or NO CHANGE. Chooseone of the available settings andpress the set/reset button while it isdisplayed on the DIC to select it.



FAST IDLE ON

If your vehicle has this feature, thismessage displays when the fast idlefeature is on. See “Fast Idle Control”under Starting the Diesel Engine onpage 9‑1.

Transmission Messages

SHIFT INHIBITED SELECT NTO RESET (Pickup Models)

If the transmission is unable toshift into a selected gear, thismessage will appear on the DIC.The electronic shift positionindicator on the instrument panelcluster may blink when this occurs.To make the vehicle shift to therequested gear, you may have toshift back to P (Park) or N (Neutral)and re-select the desired gear.

Vehicle Speed Messages

89 KM/H (55MPH) MAX SPEEDUPON RESTART

This message will be displayedalong with other messages.These messages include EXHAUSTFLUID EMPTY REFILL NOW,EXHAUST FLUID QUALITY POOR,or SERVICE EXHAUST FLUIDSYSTEM. The vehicle speed will belimited to 89 KM/H (55 MPH) at thenext restart.

7 KM/H (4 MPH) MAX SPEEDNEXT FUEL FILL

This message will be displayedalong with other messages.These messages include EXHAUSTFLUID EMPTY REFILL NOW,EXHAUST FLUID QUALITY POOR,or SERVICE EXHAUST FLUIDSYSTEM. The vehicle speed will belimited to 7 KM/H (4 MPH) at thenext fuel fill.

SPEED LIMITED TO89 KM/H (55MPH)

This message will be displayedalong with other messages.These messages include EXHAUSTFLUID EMPTY REFILL NOW,EXHAUST FLUID QUALITY POOR,or SERVICE EXHAUST FLUIDSYSTEM. When this message isdisplayed, the vehicle speed isbeing limited to 89 KM/H (55 MPH).

SPEED LIMITED TO7KM/H (4 MPH)

This message will be displayedalong with other messages.These messages include EXHAUSTFLUID EMPTY REFILL NOW,EXHAUST FLUID QUALITY POOR,or SERVICE EXHAUST FLUIDSYSTEM. When this message isdisplayed, the vehicle speed isbeing limited to 7 KM/H (4 MPH).



VehiclePersonalizationYour Duramax Diesel vehicle mayhave additional customizablefeatures for Power Take-Off (PTO).See Power Take-Off (PTO) onpage 9‑42 for more information.

Entering the FeatureSettings Menu

1. Turn the ignition on and placethe vehicle in P (Park).

To avoid excessive drain on thebattery, it is recommended thatthe headlamps are turned off.

2. Press the customization buttonto scroll through the availablecustomizable options.

Feature Settings Menu Items

PTO STANDBY SPEED

This feature allows you to select thePTO standby speed.

Press the customization button untilthe PTO STANDBY SPEED screenappears on the DIC display. Pressthe set/reset button once to accessthe settings for this feature. Thenpress the customization button toscroll through the following choices:. 800 RPM. 900 RPM. 1000 RPM. 1100 RPM. 1200 RPM. 1300 RPM. 1400 RPM. 1500 RPM. NO CHANGE

To select a setting, press theset/reset button while the desiredsetting is displayed on the DIC.

PTO SET 1 SPEED

This feature allows you to select thePTO 1 set speed.

Press the customization button untilthe PTO SET 1 SPEED screenappears on the DIC display. Pressthe set/reset button once to accessthe settings for this feature. Thenpress the customization button toscroll through the following choices:. 1000 RPM. 1200 RPM. 1400 RPM. 1600 RPM. 1800 RPM. 2000 RPM. 2200 RPM. 2400 RPM. NO CHANGE




PTO SET 2 SPEED

This feature allows you to select thePTO 2 set speed.

Press the customization button untilthe PTO SET 2 SPEED screenappears on the DIC display. Pressthe set/reset button once to accessthe settings for this feature. Thenpress the customization button toscroll through the following choices:. 1800 RPM. 2000 RPM. 2200 RPM. 2400 RPM. 2600 RPM. 2800 RPM. 3000 RPM. 3200 RPM. NO CHANGE


PTO TAP STEP

This feature allows you to select thePTO tap step.

Press the customization buttonuntil the PTO TAP STEP screenappears on the DIC display. Pressthe set/reset button once to accessthe settings for this feature. Thenpress the customization button toscroll through the following choices:. 25 RPM. 75 RPM. 100 RPM. 150 RPM. 200 RPM. 250 RPM. 350 RPM. NO CHANGE


PTO SHUTDOWN TIME

This feature allows you to select thePTO shutdown time.

Press the customization button untilthe PTO SHUTDOWN TIME screenappears on the DIC display. Pressthe set/reset button once to accessthe settings for this feature. Thenpress the customization button toscroll through the following choices:. OFF. 20 MINUTES. 35 MINUTES. 50 MINUTES. 65 MINUTES. 80 MINUTES. 95 MINUTES. 110 MINUTES. NO CHANGE



Driving and Operating 9-1

Driving andOperating

Starting and OperatingStarting the Diesel Engine . . . . 9-1Winter Cover . . . . . . . . . . . . . . . . . . 9-5Engine Heater . . . . . . . . . . . . . . . . . 9-9Fuel Operated Heater (FOH)(Van Models Only) . . . . . . . . . 9-10

Parking Over ThingsThat Burn . . . . . . . . . . . . . . . . . . 9-10

Engine ExhaustDiesel Particulate Filter(Exhaust Filter) . . . . . . . . . . . . . 9-10

Diesel Exhaust Fluid . . . . . . . . . 9-12

BrakesExhaust Brake(Pickup Models Only) . . . . . . 9-16

FuelFuel for Diesel Engines . . . . . . 9-17What Fuel to Use inThe U.S. . . . . . . . . . . . . . . . . . . . 9-18

What Fuel to Use inCanada and Mexico . . . . . . . . 9-22

Cold Weather Operation . . . . . 9-27Water in Fuel . . . . . . . . . . . . . . . . 9-27Running Out of Fuel . . . . . . . . . 9-32Fuel Filter Replacement . . . . . 9-33Filling the Tank . . . . . . . . . . . . . . 9-35Filling a Portable FuelContainer . . . . . . . . . . . . . . . . . . . 9-37

TowingTrailer Towing . . . . . . . . . . . . . . . . 9-37

Conversions and Add-OnsPower Take-Off (PTO) . . . . . . . 9-42

Starting andOperating

Starting the DieselEngineThe diesel engine starts differentlythan a gasoline engine. The vehiclewill only start in the P (Park) or theN (Neutral) position.

Move the shift lever to P (Park) orN (Neutral). To restart the enginewhen the vehicle is already moving,use N (Neutral) only.

Notice: Do not try to shift toP (Park) if the vehicle is moving.If you do, you could damage thetransmission. Shift to P (Park)only when the vehicle is stopped.


9-2 Driving and Operating

Starting the Engine

1. Turn the ignition key to ON/RUN.

Observe the wait to start light.See Wait-to-Start Light onpage 5‑9. This light may notcome on if the engine is warm.

2. As soon as the wait to start lightgoes off, immediately turn theignition key to START. When theengine starts, let go of the key.

The engine has a fast warm-upglow plug system. The wait tostart light will illuminate for amuch shorter time than mostdiesel engines, due to the rapidheating of the glow plug system.

Notice: If the wait to start lightstays on after starting the vehicle,the vehicle may not run properly.Have the vehicle servicedright away.

3. If the engine does not start after15 seconds of cranking, turn theignition switch to LOCK/OFF.Wait one minute for the starter tocool, then try the same stepsagain.

If you are trying to start the engineafter you have run out of fuel, followthe steps in Running Out of Fuel onpage 9‑32.

When the engine is cold, let it runfor a few minutes before you movethe vehicle. This lets oil pressurebuild up. The engine will soundlouder when it's cold.

Notice: If you are not in an idlingvehicle and the engine overheats,you would not be there to see theoverheated engine indication.This could damage the vehicle.Do not let the engine run whenyou are not in the vehicle.

Cold Weather Starting(Diesel Engine)

The following tips will help withcold weather starting.

Use the recommended engine oilwhen the outside temperaturedrops below freezing. See EngineOil on page 10‑7. When theoutside temperature drops below–18°C (0°F), use of the enginecoolant heater is recommended.

If you experience longer crankingtimes, notice an unusual amount ofexhaust smoke or are at higherelevations (over 2 135 m or7,000 ft.), you may use the enginecoolant heater. See Engine Heateron page 9‑9.

See Fuel for Diesel Engines onpage 9‑17 for information on whatfuel to use in cold weather.



If the Diesel Engine Will NotStart

If you have run out of fuel, seeRunning Out of Fuel on page 9‑32.

If the vehicle is not out of fuel, andthe engine will not start, do this:

Turn the ignition key to ON/RUN.Immediately after the wait to startlight goes off, turn the ignition keyto START.

If the light does not go off, wait afew seconds, then try starting theengine again. See your dealer assoon as you can for a startingsystem check.

If the light comes on and then goesoff and you know the batteries arecharged, but the engine still will notstart, the vehicle needs service.

If the light does not come on whenthe engine is cold, the vehicleneeds service.

If the batteries don't have enoughcharge to start the engine, see“Battery” in the Index of the vehicleowner manual.

Be sure you have the right oil for theengine, and that you have changedthe oil at the proper times. If youuse the wrong oil, the engine maybe harder to start.

Be sure you are using the properfuel for existing weather conditions.See Fuel for Diesel Engines onpage 9‑17.

If the engine starts, runs a shorttime, then stops, the vehicle needsservice.

{ WARNING

Do not use gasoline or startingaids, such as ether, in the airintake. They could damage theengine. There could also be afire, which could cause seriouspersonal injury.

Elevated Idle

The engine has a cold temperaturehigh idle feature which elevates theengine idle speed from base idleto 1050 rpm for pickup models or1200 rpm for van models whenoutside temperatures are below0°C (32°F), and the engine coolanttemperature is below 65°C (150°F).This feature enhances heaterperformance by raising the enginecoolant temperature faster.

This feature can be turned on or offusing the DIC buttons. If the vehicleis not equipped with DIC buttons, dothe following to turn this feature onor off:

1. Turn the ignition to ON/RUN,with the vehicle off.

2. Press the accelerator pedal tothe floor and hold while quicklypressing the brake pedal threetimes in less than eight seconds.

3. Release the accelerator pedaland start the engine.



When the engine is started, it willslowly ramp up to the high idlespeed after a delay of a fewseconds up to approximatelytwo minutes. For this method towork properly there must be nothrottle or brake pedal faults.

The engine idle speed will return tonormal once the following conditionsare met:. Once engine coolant

temperature reaches65°C (150°F).

. Air intake temperaturereaches 0°C (32°F).

The high idle speed will betemporarily interrupted and theengine speed will return to normalif any of the following conditionsoccur:. The brake pedal is applied.. The accelerator pedal is

pressed.. The transmission is shifted out

of P (Park) or N (Neutral).. Vehicle speed is detected.

Once these inputs are removed, theengine idle speed will slowly rampback up to high idle after the normaldelay, if the conditions for enginecoolant temperature and air intaketemperature are still met.

Fast Idle Control

The vehicle may have this systemwhich can be used to increase theengine idle speed.

Fast Idle control will be enabledwhen the following conditionsare met:. The park brake is set.. The transmission is in P (Park)

or N (Neutral).. The vehicle speed is about

0 km/h (0 mph).. The cruise control is in the On

position. See “Cruise Control” inthe Index of the vehicle ownermanual.

. The cruise control Set switch ispressed and released for PresetFast Idle Speed (1200 rpm).

Fast Idle control will be disabledwhen one or more of the followingconditions occur:. The cruise control is in the Off

position.. The cruise control Set switch is

pressed and released. See“Cruise Control” in the Index ofthe vehicle owner manual.

. The cruise control Cancel switchis pressed.

. The brake pedal is pressed.

. The transmission is shifted outof P (Park) or N (Neutral).

. The park brake is released.

. The vehicle speed is not0 km/h (0 mph).

When Fast Idle is active, a FASTIDLE ON message will be displayedin Driver Information Center (DIC).See Starting the Vehicle Messageson page 5‑13.



Winter CoverIf the vehicle includes a wintercover, it can be used to enhanceheater performance in extremelycold conditions below −18°C (0°F).The winter cover installs over thegrille and restricts air flow to theengine compartment.

For diesel powered vehicles thatdid not come with a winter cover, aGM winter cover can be purchasedas an accessory. See your dealerfor additional information.

Usage Guidelines

The winter cover should only beused while operating the vehicle inextremely cold temperatures or inheavy snow for extended periods oftime. In these temperatures, thevehicle does not need a largeamount of air to properly cool theengine. When more airflow isrequired to cool the vehicle, thewinter cover should not be used.

The following usage guidelines willallow adequate airflow for properradiator and air cooler performance:. Do not use the winter cover if

towing a trailer. The addedpower needed to tow a trailerrequires the radiator grille tohave full airflow under allconditions. The vehicle mayoverheat if the cover is usedwhile towing a trailer.

. Do not modify the cover. Thewinter cover does not coversome sections of the front of thevehicle because these openingsare needed to provide enoughairflow to the radiator grille andair cooler in extremely coldtemperatures.

. When the winter cover is used,the temperature sensor foundon the inside rearview mirrorwill not function properly. Thetemperature that is shown willbe incorrect.

. Keep the underside of the wintercover as clean as possible at alltimes. Remove monthly or asnecessary and clean away dustand debris.

. Use only a mild soap to cleanthe winter cover. Do not useharsh soap, strong detergents orvinyl protectant/sealant typeproducts as they may destroythe special finish of the wintercover. Allow the winter cover todry completely before reinstallingon the vehicle.

Installation Instructions

When you first try to fit the cover itmay appear to be undersized.This is due to the nature of thespecial vinyl, which will stretchduring installation to ensure a tightfit. For this reason, the initialinstallation of the cover is bestperformed when the winter coveris warm.



Installation (Chevrolet Pickup)

Open the hood.

A. Slide the channels of the coverdown the back edge of the grilleon both sides.

B. Hook J-clips to the bottom ofthe grille.

C. Hook J-clips on to the top edgeof the grille by the enginecompartment.



D. Hook J-clips to the side edge ofthe grille.

E. To remove the winter cover,reverse the steps listedpreviously.

Installation (GMC Pickup)

Open the hood.

A. Slide the channels of the coverdown the back edge of the grilleon both sides.

B. Insert pockets between thegrille and the bumper.

C. Hook J-clips on to the top edgeof the grille by the enginecompartment.



D. To remove the winter cover,reverse the steps listedpreviously.

Installation (Van Models)

Open the hood and secure it withthe prop rod.

A. Hook the 5 J‐clips on to thebottom edge of the grille.

B. Hook the top center J‐clip bythe hood latch.



C. Attach the metal hooks,one each at the top corners.

D. To remove the winter cover,reverse the steps listedpreviously.

Engine HeaterThe engine coolant heater canprovide easier starting and betterfuel economy during enginewarm-up in cold weather conditionsat or below −18°C (0°F). Vehicleswith an engine coolant heatershould be plugged in at leastfour hours before starting.

To Use the Engine Heater

1. Turn off the engine.

2. Open the hood and unwrapthe electrical cord. The cordis located in the enginecompartment, on thepassenger's side of thevehicle, near the right sideauxiliary battery.

3. Plug it into a normal, grounded110-volt AC outlet.

{ WARNING

Plugging the cord into anungrounded outlet could cause anelectrical shock. Also, the wrongkind of extension cord couldoverheat and cause a fire. Youcould be seriously injured. Plugthe cord into a properly groundedthree-prong 110-volt AC outlet.If the cord will not reach, use aheavy-duty three-prong extensioncord rated for at least 15 amps.

4. Before starting the engine, besure to unplug and store thecord as it was before to keep itaway from moving engine parts,and prevent damage.

The length of time the heater shouldremain plugged in depends on theoutside temperature. You may wishto use the coolant heater to improveease of starting at temperaturesbetween −18°C (0°F) and −29°C(−20°F). Keep the coolant heaterplugged in for a minimum of fourhours. At temperatures below−29°C (−20°F), the coolant heatershould remain plugged in for at leasteight hours. It will not harm eitherthe coolant heater or the vehicle toleave the coolant heater pluggedin longer than the times stated.Be sure to remove and store thecord before starting the engine.See Fuel for Diesel Engines onpage 9‑17 for information on whatfuel to use in cold weather.



Fuel Operated Heater(FOH) (Van Models Only)

If the vehicle includes an FOH, it willenhance heater performance andwill reduce the amount of time ittakes to warm the inside of thevehicle in cold conditions below orequal to 4°C (39°F). The FOH isinstalled on the frame rail on thedriver side of the vehicle and usesdiesel fuel to heat the enginecoolant, which warms up thepassenger cabin air.

The FOH will turn on if all of thefollowing conditions exist:. Outside air temperature is below

or equal to 4°C (39° F).. Fuel level is greater or equal to

12.5 percent of the total fuel tankvolume.

. The engine is running.

. Coolant temperature is less than75°C (167° F).

Parking Over ThingsThat Burn

{ WARNING

Things that can burn could touchhot exhaust parts under thevehicle and ignite. Do not parkover papers, leaves, dry grass,or other things that can burn.

Engine Exhaust

Diesel Particulate Filter(Exhaust Filter)The vehicle has a Diesel ParticulateFilter (DPF) as part of the exhaustsystem to reduce vehicle emissions.The DPF requires a unique exhausttailpipe with an exhaust cooler.The exhaust cooler mixes airwith the exhaust to lower thetemperature before it leaves thetailpipe.

The DPF, the tailpipe, or otherexhaust system components mustnot be altered. Inspect regularly andclean any mud or dirt from theexhaust cooler, especially wherethe exhaust cooler connects tothe tailpipe and the openingswhere fresh air enters the cooler.See “Exhaust System Inspection”under Scheduled Maintenance onpage 11‑2.



The DPF will clean itself as part ofnormal operation. Several factorsincluding fuel consumed, hours ofengine operation and miles drivenare monitored by the Engine ControlModule (ECM). The self-cleaningoccurs approximately once per tankof fuel.

Notice: Permanent damage canoccur to the DPF or relatedcomponents if the required UltraLow Sulfur Diesel (15 ppm sulfurmaximum) or low ash CJ‐4 engineoil is not used. This damagewould not be covered by thevehicle warranty.

Under certain driving conditions,such as stop and go traffic, the filtercannot clean itself. The CLEANINGEXHAUST FILTER KEEP DRIVINGUNTIL MESSAGE IS CLEAREDmessage comes on when the DPFis dirty and needs to perform aself‐cleaning.

For the filter to clean itself, thevehicle must be driven above50 km/h (30 mph) until theCLEANING EXHAUST FILTERKEEP DRIVING UNTIL MESSAGEIS CLEARED message goes off.This will take about 30 minutes.

{ WARNING

During DPF self cleaning orduring extended idling in P (Park),the exhaust system and exhaustgases are very hot. Things thatburn could touch hot exhaustparts under the vehicle and ignite.You or others could be burned.Do not park, or idle for anextended period of time, near orover papers, leaves, dry grass,or other things that can burn.Keep the exhaust area clear ofmaterial that could ignite or burn.See Parking Over Things ThatBurn on page 9‑10 for moreinformation.

Notice: Extended idle should beavoided because the DPF systemis not capable of self cleaningat idle. During extended idleoperation, monitor the instrumentpanel telltale lights and DriverInformation Center for messagesand take appropriate indicatedaction. Continued idling with thewarning light/message on couldcause irreversible damage to theDPF requiring repair and possiblereplacement that might not becovered by the vehicle warranty.

You will also notice a change in theexhaust sound and engine idlespeed. This is normal. See VehicleMessages on page 5‑11.



If you continue to drive with theDPF warning message on and theexhaust filter is not cleaned asrequired, the Malfunction IndicatorLamp and the ENGINE POWER ISREDUCED message will come onand dealer service is necessary.See Malfunction Indicator Lamp onpage 5‑6 and Engine PowerMessages on page 5‑11.

Vehicles with DPF have specificfuel and engine oil requirements.See What Fuel to Use in The U.S.on page 9‑18 or What Fuel to Use inCanada and Mexico on page 9‑22and Engine Oil on page 10‑7 formore information on thoserequirements.

Extended idling in P (Park) cancause exhaust parts and gases tobecome very hot. Keep the exhaustarea clear of material that couldignite or burn. See Parking OverThings That Burn on page 9‑10 formore information.

For vehicles with Power Take‐Off(PTO), monitor the instrument panelcluster for lights related to the DPF.

All engines consume some amountof engine oil. Ash is the by‐productof engine oil combustion. The ashwill become trapped in the DPF overthe life of the vehicle. Eventually,the buildup of ash will restrict theexhaust gases and the DPF willneed to be cleaned or replaced.

See Accessories and Modificationson page 10‑2 for importantinformation if you are consideringadding accessories or modifyingthe vehicle.

Diesel Exhaust Fluid

{ WARNING

Diesel Exhaust Fluid (DEF) iscorrosive. Do not allow it tocome in contact with your skin,eyes, or the finished surfaces ofthe vehicle. If exposed, it maycause skin and eye irritation.Wear skin and eye protectionwhen handling. Inhalation maycause irritation to the upperrespiratory tract. Store in a cool,well‐ventilated area. For moresafety information, see the labelof the Diesel Exhaust Fluidcontainer.

Diesel Exhaust Fluid (DEF) is usedwith diesel engines to reduce theamount of regulated emissionsproduced. The fluid level in theDEF tank must be maintained forthe vehicle to run correctly.

The capacity of the DEF tank isapproximately 18.9 L (5 gal).



Locating Diesel Exhaust Fluid

DEF can be purchased at aChevrolet or GMC dealer. It canalso be purchased at authorizedvehicle and truck dealerships.Additionally, some diesel truckfuelling stations or retailers mayalso have DEF for purchase.For vehicles with an active OnStarsubscription, OnStar can help tolocate a DEF retailer. For moreinformation on locating DEF seewww.afdc.energy.gov/afdc/vehicles/diesels_fluid.html. See “CustomerAssistance Offices” in the ownermanual for phone numbers to assistyou in contacting a GM dealer.See Recommended Fluids andLubricants on page 11‑8.

Filling the DEF Tank

Notice: Use only exhaust fluidthat is GM approved, or fluidcontaining the API certified orISO 22241 label. The use of otherfluids could damage the system,requiring costly repairs that willnot be covered by the vehiclewarranty.

When adding DEF to an empty orvery low tank, always add at least3.78 liters (one gallon) of fluid torelease the vehicle from speedlimitation.

Do not over fill the DEF tank.When fluid reaches the top of thefill pipe, stop filling. Do not top offthe DEF tank.

If you spill DEF on the vehicle whilefilling the tank, wipe the surface witha damp cloth.

DEF Fill ‐ Vans

For vans, the DEF fill is locatedbehind the fuel fill door. The DEFcap is blue, and diesel cap is green.

Fill tube location for chassis‐caband cutaway vans finished by anupfitter will vary. Check the upfittersmanual.



DEF Fill ‐ Pickups

For full sized pickups, the DEF fill islocated under the hood, on thepassenger side, at the back of theengine compartment. The DEF capis blue.

Exhaust Fluid Low Warnings

A full DEF tank will last for severalthousand kilometers (miles),depending on vehicle usage.As the exhaust fluid level drops,warnings will be displayed in theDIC. There will not be any DEFrange DIC messages with morethan 1600 km (1000 miles) of DEFrange remaining. DIC messagesbegin with approximately 1600 km(1000 miles) of range and, as thetank becomes empty, vehicle speedlimitation will result.

To avoid vehicle speed limitations,the DEF tank should be refilled atthe first opportunity after a lowwarning indication.

If DEF is added before theEXHAUST FLUID EMPTY messageappears, it may take severalkm/miles for the DIC message toupdate.

If the vehicle speed has beenlimited and DEF has been added,it may take up to 30 seconds after

engine start, with the vehiclestopped, for the EXHAUST FLUIDEMPTY message to clear. If thevehicle is driven prior to the DICmessage clearing, the vehiclespeed will still be limited. If the DICmessage clears while driving, thevehicle must be completely stoppedto remove the speed limitation.

If DEF is added under freezingconditions, additional time maybe required to remove speedlimitations.

A DIC message EXHAUSTFLUID RANGE: XXX will bedisplayed at approximately1600 km (1000 miles) of fluid rangeremaining. This message willappear again at approximately500 km (300 miles) of rangeremaining before the exhaust fluidtank becomes empty.

Below 500 km (300 miles) of rangeremaining, these messages willappear every time the vehicle isstarted.



If these warnings are ignored andthe DEF tank becomes empty, aDIC message 89 km/h (55 mph)MAX SPEED UPON RESTARTwill be displayed. There will alsobe a warning light and chime.The vehicle will be speed limited to89 km/h (55 mph) at the next restart.

When adding DEF to an empty orvery low tank, always add at least3.78 liters (one gallon) of fluid torelease the vehicle from speedlimitation. The capacity of the DEFtank is approximately 18.9 L (5 gal).

If the vehicle continues to be drivenwithout filling the DEF tank, it will belimited to 7 km/h (4 mph) after thesecond fuel fill.

See Vehicle Messages onpage 5‑11, Diesel Exhaust Fluid(DEF) Warning Light on page 5‑9and Recommended Fluids andLubricants on page 11‑8 for moreinformation.

Exhaust Fluid Quality Poor

Use only exhaust fluid that isGM approved, or fluid containing theAPI certified or ISO 22241 label.

All DEF has an expiration date.If the system detects poor quality,contaminated or diluted DEF, theDIC will display EXHAUST FLUIDQUALITY POOR. SEE OWNERSMANUAL NOW. Adding fresh DEFto the system may resolve theproblem, depending on severalfactors. If the DIC message persists,see your dealer.

After 322 km (200 miles) of drivingwithout correcting the problem, aDIC message 89 km/h (55 mph)MAX SPEED UPON RESTART willbe displayed. There will also be awarning light and chime. Thevehicle will be speed limited to89 km/h (55 mph) at the next restart.

If the problem is not resolvedafter 805 km (500 miles) ofoperation, speed will be limited to7 km/h (4 mph) after the next fuel fill.

Service Exhaust Fluid System

If a problem occurs with theDEF system, the DIC will displaySERVICE EXHAUST FLUIDSYSTEM SEE OWNERS MANUALNOW. In some cases this messagewill clear itself, indicating that theDEF system was able to correct thecondition. If the DIC messagepersists, see your dealer.

After 322 km (200 miles) of drivingwithout correcting the problem, aDIC message 89 km/h (55 mph)MAX SPEED UPON RESTART willbe displayed. There will also be awarning light and chime. Thevehicle will be speed limited to89 km/h (55 mph) at the next restart.

If the problem is not resolved after805 km (500 miles) of operation,speed will be limited to 7 km/h(4 mph) after the next fuel fill.



Brakes

Exhaust Brake(Pickup Models Only)The heavy duty diesel pickups havean exhaust brake to enhance thevehicle brake system, and reducebrake lining wear. A switch is usedto activate the system, and islocated below the climate controls inthe center of the vehicle instrumentpanel. The switch must be pressedat each vehicle start for the systemto be active. A light in the switch willcome on when the Exhaust Brakeis activated.

The Driver Information Center(DIC) displays the messageEXHAUST BRAKE ENABLEDfor approximately 10 seconds,then clears.

To turn the brake off, press theexhaust brake switch a second time.The DIC displays the messageEXHAUST BRAKE DISABLED forapproximately 10 seconds, thenclears.

Downshifts may be automaticallyselected to increase engine speed,which increases the effectiveness ofthe exhaust brake. The number of

downshifts selected is determinedby the length of time the vehiclesbrakes are applied, and the rate thevehicle is slowing. The systemdelivers the correct amount ofbraking to assist in vehicle control.The heavier the vehicle load, themore active the engine exhaustbrake will be. Use of the exhaustbrake will help maintain vehiclespeed when used with cruisecontrol. See Tow/Haul Mode in thevehicle owner manual.

Automatic downshifts will not occurif the vehicle is in Range SelectionMode. See Manual Mode in thevehicle owner manual.

The exhaust brake only activateswhen the transmission torqueconverter is locked. This canvary based on vehicle speed,gear and load. The exhaust brakewill be more active when inTow/Haul Mode.



Fuel

Fuel for Diesel EnginesSome states and provinces haverestrictions on the purchase ofdiesel fuel for light-duty vehicles andrequire you to buy permits or payspecial taxes. Some of theserestrictions apply only to residents,and others apply to both residentsand visitors. These restrictions canchange. To learn the currentrestrictions in any state or province,contact your auto club, the police,or other officials.

Notice: Diesel fuel or fueladditives not recommended inthis manual could damage thefuel system, fuel‐operated heater(FOH) (Van models only), andengine. Your warranty would notcover this damage. And:. Diesel fuel that has beenmixed with engine oil orautomatic transmission fluidcould damage the engineand emission controls.

. We do not test aftermarketdiesel fuel additives. Someadditives, particularly thosewhich contain alcohol orwater emulsifiers, coulddamage the fuel system.If you believe that uniquecircumstances call for a fueladditive to be used, consultyour dealer for advice.

. If you ever run out of dieselfuel, it can be difficult torestart the engine. To avoidthis, never let the tank getempty.

If gasoline is ever accidentallyadded to the fuel tank, to avoidsevere engine damage, do notrun the engine until the fuel tankcan be drained.

Some conditions, such as dirty fuel,may decrease fuel filter life and achange filter message maycome on.

If you run out of fuel, Running Out ofFuel on page 9‑32 tells you how torestart the engine.



What Fuel to Use inThe U.S.Notice: Use of diesel fuel otherthan Ultra Low Sulfur Diesel(15 ppm sulfur maximum) willcause permanent damage to theexhaust after‐treatment system.This damage would not becovered by the vehicle warranty.

The emission control systemrequires the use of diesel fuel withultra low sulfur content (15 ppm or0.0015% by weight, maximum).

Look for the following label on thedispenser to ensure you are fillingwith Ultra Low Sulfur Diesel fuel.

At a minimum, the diesel fuel youuse should meet the latest versionof ASTM specification D 975(Grades No. 2‐D or No. 1‐D S15,commonly known as Ultra LowSulfur Diesel) in the United States.If there are questions about the fuelyou are using, contact your fuelsupplier.

Diesel Fuel Grades

For best results use No. 2‐D dieselfuel year-round (above and belowfreezing conditions) as oilcompanies blend No. 2‐D fuel toaddress climate differences. No. 1‐Ddiesel fuel can be used in very coldtemperatures (when it stays below−18°C or 0°F); however, it willproduce a power and fuel economyloss. Avoid the use of No. 1‐D dieselfuel in warm or hot climates. It canresult in stalling, poor starting whenthe engine is hot, and could damagethe fuel injection system.

Premium Diesel Fuel

Diesel fuel corresponding to theEngine Manufacturers Association(EMA) Recommended Guideline onPremium Diesel Fuel (FQP‐1A)could provide better starting,less noise, and better vehicleperformance, but its use is notrequired.



Biodiesel

What is biodiesel?

Biodiesel is a fuel produced fromvegetable oils or animal fats thathave been chemically modified toreduce the possibility of damage tothe fuel system and engine.

Notice: Raw vegetable oil orother unmodified bio-oils or fatsare not biodiesel and must not beused in your vehicle as theycould damage the fuel systemand engine.

What not to use

Do not use home‐made biodiesel inyour vehicle since its quality cannotbe verified by approved scientificmethods. Home test kits are notapproved scientific methods.

Notice: Any damage caused byraw, unmodified, or home-madebiodiesel would not be coveredby the vehicle warranty.

Biodiesel blends

It is acceptable to use diesel fuelcontaining up to 20% biodiesel(B20). The diesel fuel portion ofthe blend must meet the samespecification, ASTM D975(Grades No. 2‐D or No. 1‐D S15commonly known as Ultra LowSulfur Diesel), as other fuels used inyour vehicle, and the biodiesel usedfor making this fuel must meet thelatest version of ASTM specificationD6751.

. Pump labeling — Retail pumpsdispensing blends containing upto 5% biodiesel (B5) are notrequired to be labeled with theconcentration of biodiesel.Blends up to B5 must meetASTM D975 (Grades No. 2‐D orNo. 1‐D S15 commonly knownas Ultra Low Sulfur Diesel).

Notice: Do not use blendscontaining more than20% biodiesel. Any engine,fuel system, or exhaustafter-treatment system damagecaused by the use of such blendswould not be covered by thevehicle warranty.

Pumps dispensing more than5% and up to 20% biodiesel arerequired to be labeled with theconcentration of biodiesel.



When refueling with a biodieselblend above B5, ensure one ofthe following two labels appearson the dispenser:

. Biodiesel quality — Blendscontaining more than 5% andup to 20% biodiesel must meetthe latest version of ASTMspecification D7467 (Biodieselblend, B6 ‐ B20). Biodiesel isan emerging product, and itsquality can vary widely.To reduce the risk of poorquality fuel, we recommend thatbiodiesel users purchasebiodiesel blends from a BQ‐9000certified marketer. A listing ofcertified marketers can be foundat www.bq‐9000.org. If thereare questions about thebiodiesel‐containing fuels youare using, contact your fuelsupplier.

Notice: Certain drivingpatterns are not compatiblewith biodiesel use. It is theoperator’s responsibility toensure that biodiesel in thevehicle’s tank does not lead toengine, fuel system, or exhaustafter‐treatment system damage.

We neither encourage nordiscourage the use of biodieselblends for vehicles. As a renewablefuel, biodiesel provides someenvironmental benefits. However,biodiesel has unique properties andneeds to be handled differently thandiesel fuel. Its use presentsadditional risks and may not beappropriate in all situations. Certainvehicle operating modes increasethese risks and should be avoided.Read further to determine if yourdriving habits are compatible withthe use of biodiesel.



. Biodiesel fuel quality degradeswith time and exposure to hightemperature much more quicklythan conventional diesel fuel.More frequent refueling providesthe best opportunity to have asupply of fresh fuel.

Owners who have very low fuelusage or who have vehiclesstored for extended periods oftime should avoid the use ofbiodiesel. Storage at hot ambienttemperatures will acceleratebiodiesel degradation.

When vehicles will be storedfor extended periods of time(greater than one month), theyshould be run out of biodiesel tobelow 1/4 tank, refueled withconventional Ultra Low SulfurDiesel fuel, and driven severalmiles before storage.

. Biodiesel gels sooner thanconventional diesel fuel at coldtemperature, and biodiesel fuelrequires proper blending forwinter time operation.

Fuels improperly blended forcold temperature operation mayresult in restricted fuel filters anddegraded vehicle performance.Your vehicle is equipped with afuel heating system to provide alevel of protection against filterplugging from gelling (waxing) ofconventional diesel fuel andbiodiesel blends. However, thesystem will not prevent all casesof plugged filters if the operatingtemperature is far below thetemperature at which gellingor waxing of the fuel occurs(cloud point).

Use of biodiesel blends greaterthan B5 (5% blend) should beavoided in cold temperatures.

. Vehicles operated for extendedperiods of time on conventionaldiesel fuel and then switched tobiodiesel blends may experiencepremature fuel filter clogging andrequire more frequent fuel filterservice.

With long term use ofconventional diesel fuel, gumand varnish may be depositedwithin the tank and fuel system.These deposits, while notproblematic with the use ofconventional diesel fuel, maybecome loosened with a suddenswitch to biodiesel blends andcause fuel filter plugging.

This vehicle is equipped with afuel filter restriction monitoringsystem that will alert you if thefuel filter requires service, but itwill not prevent damage causedby poor quality biodiesel.

. Use of biodiesel blends willdegrade the performance ofyour vehicle’s water separator.Biodiesel reduces theeffectiveness of the vehicle’swater separator, and in the eventof water contamination of thefuel, increases the risk ofdamage to the fuel system.



Refueling

Diesel fuel can foam when you fillthe tank. This can cause theautomatic pump nozzle to shut off,even though the tank is not full.If this happens, wait for the foamingto stop, and then try filling the tankmore slowly. See Filling the Tank onpage 9‑35.

{ WARNING

Heat coming from the engine cancause the fuel to expand andforce the fuel out of the tank.If something ignites the fuel, a firecould start and people could beburned. To help avoid this, tryfilling the tank more slowly andfill the fuel tank only until theautomatic nozzle shuts off.Do not try to top it off.

Accidental Refueling withGasoline

If you accidentally refuel withgasoline, your vehicle will run veryrough, will produce smoke, and willhave significantly reduced power.Avoid operating the vehicle and/oroperate only at low speeds and/orlow accelerator positions. Siphon orpump as much of the gasoline fromthe tank as possible, preferablyuntil the fuel gauge reads nearE (empty). Refuel with Ultra LowSulfur Diesel fuel. Your dealer willbe able to perform this procedure.Operating your vehicle for aprolonged period of time ongasoline could result in engine orfuel system damage which wouldnot be covered by the vehiclewarranty.

What Fuel to Use inCanada and MexicoThe emission control systemrequires the use of diesel fuel withultra low sulfur content (15 ppm or0.0015% by weight, maximum).

What Fuel to Use in Canada

Notice: Use of diesel fuel otherthan Ultra Low Sulfur Diesel(15 ppm sulfur maximum) willcause permanent damage to theexhaust after‐treatment system.This damage would not becovered by the vehicle warranty.

At a minimum, the diesel fuel youuse should meet the latest versionof specification CAN/CGSB‐3.517(ULS) in Canada. If there arequestions about the fuel you areusing, contact your fuel supplier.



Diesel Fuel Types

Canadian fuels are blended forseasonal changes. Diesel Type “A”fuel is blended for better coldweather starting, below −18°C (0°F);however, you might notice somepower and fuel economy loss.If Type “A” fuel is used in warmertemperatures, stalling and hardstarting may occur. Diesel Type “B”fuel is blended for temperaturesabove −18°C (0°F).

Premium Diesel Fuel

Diesel fuels corresponding to theEngine Manufacturers Association(EMA) Recommended Guideline onPremium Diesel Fuel (FQP‐1A)could provide better starting,less noise, and better vehicleperformance, but their use is notrequired.

Biodiesel

What is biodiesel?

Biodiesel is a fuel produced fromvegetable oils or animal fats thathave been chemically modified toreduce the possibility of damage tothe fuel system and engine.

Notice: Raw vegetable oil orother unmodified bio-oils or fatsare not biodiesel and must not beused in your vehicle as theycould damage the fuel systemand engine.

What not to use

Do not use home‐made biodiesel inyour vehicle since its quality cannotbe verified by approved scientificmethods. Home test kits are notapproved scientific methods.

Notice: Any damage caused byraw, unmodified, or home-madebiodiesel would not be coveredby the vehicle warranty.



Biodiesel blends

It is acceptable to use diesel fuelcontaining up to 20% biodiesel(B20). For low level, under 5%,biodiesel blends (B1 to B5),the fuel you use should meet thelatest version of specificationCAN/CGSB‐3.520 (ULS). At thetime of printing of this manual, aCGSB standard for B6‐B20 is underdevelopment and has not beenpublished. Until a CGSB B6‐B20specification is available, biodieselblends containing more than 5%and up to 20% biodiesel mustmeet the latest version of ASTMspecification D7467 (Biodieselblend, B6‐B20). To reduce the riskof poor quality fuel, we recommendthat biodiesel users purchasebiodiesel blends from a BQ‐9000certified marketer. A listing ofcertified marketers can befound at www.bq‐9000.org.

If there are questions about thebiodiesel‐containing fuels you areusing, contact your fuel supplier.

Notice: Certain drivingpatterns are not compatiblewith biodiesel use. It is theoperator’s responsibility toensure that biodiesel in thevehicle’s tank does not lead toengine, fuel system, or exhaustafter‐treatment system damage.

We neither encourage nordiscourage the use of biodieselblends for vehicles. As a renewablefuel, biodiesel provides someenvironmental benefits. However,biodiesel has unique properties andneeds to be handled differentlythan diesel fuel. Its use presentsadditional risks and may not beappropriate in all situations. Certainvehicle operating modes increasethese risks and should be avoided.

Read further to determine if yourdriving habits are compatible withthe use of biodiesel.. Biodiesel fuel quality degrades

with time and exposure to hightemperature much more quicklythan conventional diesel fuel.More frequent refueling providesthe best opportunity to have asupply of fresh fuel.

Owners who have very low fuelusage or who have vehiclesstored for extended periods oftime should avoid the use ofbiodiesel. Storage at hot ambienttemperatures will acceleratebiodiesel degradation.

When vehicles will be storedfor extended periods of time(greater than one month), theyshould be run out of biodiesel tobelow 1/4 tank, refueled withconventional Ultra Low SulfurDiesel fuel, and driven severalmiles before storage.



. Biodiesel gels sooner thanconventional diesel fuel at coldtemperature, and biodiesel fuelrequires proper blending forwinter time operation.

Fuels improperly blended forcold temperature operation mayresult in restricted fuel filters anddegraded vehicle performance.Your vehicle is equipped with afuel heating system to provide alevel of protection against filterplugging from gelling (waxing) ofconventional diesel fuel andbiodiesel blends. However, thesystem will not prevent all casesof plugged filters if the operatingtemperature is far below thetemperature at which gelling orwaxing of the fuel occurs (cloudpoint).

Use of biodiesel blends greaterthan B5 (5% blend) should beavoided in cold temperatures.

. Vehicles operated for extendedperiods of time on conventionaldiesel fuel and then switched tobiodiesel blends may experiencepremature fuel filter clogging andrequire more frequent fuel filterservice.

With long term use ofconventional diesel fuel, gumand varnish may be depositedwithin the tank and fuel system.These deposits, while notproblematic with the use ofconventional diesel fuel, maybecome loosened with a suddenswitch to biodiesel blends andcause fuel filter plugging.

This vehicle is equipped with afuel filter restriction monitoringsystem that will alert you if thefuel filter requires service, but itwill not prevent damage causedby poor quality biodiesel.

. Use of biodiesel blends willdegrade the performance ofyour vehicle’s water separator.Biodiesel reduces theeffectiveness of the vehicle’swater separator, and in the eventof water contamination of thefuel, increases the risk ofdamage to the fuel system.



What Fuel to Use in Mexico

Notice: Use of diesel fuel otherthan Ultra Low Sulfur Diesel(15 ppm sulfur maximum) willcause permanent damage to theexhaust after‐treatment system.This damage would not becovered by the vehicle warranty.

Ultra Low Sulfur Diesel fuel is notavailable in all regions of Mexico.

Refueling

Diesel fuel can foam when you fillthe tank. This can cause theautomatic pump nozzle to shut off,even though the tank is not full.If this happens, wait for the foamingto stop, and then try filling the tankmore slowly. See Filling the Tank onpage 9‑35.

{ WARNING

Heat coming from the engine cancause the fuel to expand andforce the fuel out of the tank.If something ignites the fuel, a firecould start and people could beburned. To help avoid this, tryfilling the tank more slowly andfill the fuel tank only until theautomatic nozzle shuts off.Do not try to top it off.

Accidental Refueling withGasoline

If you accidentally refuel withgasoline, your vehicle will run veryrough, will produce smoke, and willhave significantly reduced power.Avoid operating the vehicle and/oroperate only at low speeds and/orlow accelerator positions. Siphon orpump as much of the gasoline fromthe tank as possible, preferablyuntil the fuel gauge reads nearE (empty). Refuel with Ultra LowSulfur Diesel fuel. Your dealer willbe able to perform this procedure.Operating your vehicle for aprolonged period of time ongasoline could result in engine orfuel system damage which wouldnot be covered by the vehiclewarranty.



Cold Weather OperationFollow the instructions listedpreviously under the heading“What Fuel to Use.”

Notice: Never use home heatingoil or gasoline in the vehicle.They can cause engine damagenot covered by the vehiclewarranty.

In cold weather, the fuel filter couldbecome clogged by wax naturallypresent in the fuel. To unclog it,move the vehicle to a warm garagearea and allow the filter to warm upto between 0°C (32°F) and 10°C(50°F). You will not need to replacethe filter. Additional information onthe fuel filter follows.

Use of biodiesel blends greater thanB5 (5% blend) should be avoided incold temperatures.

Water in Fuel

{ WARNING

Diesel fuel containing water is stillflammable. You could be burned.If you ever try to drain water fromthe fuel, keep sparks, flames, andsmoking materials away from themixture.

Notice: If there is water in thediesel fuel and the weather iswarm or humid, fungus andbacteria can grow in the fuel.They can damage the fuel systemand fuel operated heater (FOH)(if equipped). A diesel fuel biocidecan be used to sterilize the fuelsystem. However, the fuel systemmay still need to be cleaned.Your dealer can advise you of theappropriate solution.

If the fuel tank needs to bepurged to remove water, see yourdealer or a qualified technician.Improper purging can damage thefuel system and block the FOH.

Sometimes, water can be pumpedinto the fuel tank along with thediesel fuel. This can happen if aservice station does not regularlyinspect and clean its fuel tanks, or ifit gets contaminated fuel from itssuppliers.

If this happens, a WATER IN FUELSERVICE REQUIRED message willappear on the Driver InformationCenter (DIC). The water must bedrained.



Water in Fuel Light Chart

If the WATER IN FUEL SERVICEREQUIRED message comes on,use this chart.

ProblemRecommended

Action

Message comeson but does notremain on afteran ignitioncycle.

Water separatoris approximatelyhalf full. Drainwater as soonas possible.Water level maycontinue toincrease.

Message remains on after anignition cycle:

At temperaturesabove freezing.

Drain fuel filterimmediately.If no water canbe drained andmessage stayson, see yourdealer forassistance.

ProblemRecommended

Action

At temperaturesbelow freezing.

Drain fuel filterimmediately.If no water canbe drained,water may befrozen in waterdrain system orfuel lines. Movethe vehicle to awarm location tothaw out, andthen drain filtersystem.

Immediatelyafter refueling,large amount ofwater possiblypumped intofuel tank.

Fuel tankpurgingrequired.See your dealerfor assistance.

Notice: Driving when thiswarning indicator is on, candamage the fuel injection systemand the engine. If the indicatorcomes on right after a refuel, itmeans water was pumped intothe fuel tank. Turn off the engineimmediately. Then, have the waterdrained at once.

To drain water:

1. Stop and park the vehicle in asafe place. Turn off the engineand apply the parking brake.

2. Remove the fuel cap.

3. Place a fuel-resistantcontainer under the fuel filter(s).For pickup models, the filterdrain valve is located in theengine compartment, on thepassenger side of the vehicle,on the bottom of the fuel filter.



For van models, the filter drainvalves for the primary andsecondary fuel filters are locatedin the chassis (inside frame rail)compartment. They are on thedriver side of the vehicle, belowthe fuel filters.

4. For pickup models, open thedrain valve by turning it two tothree turns. Pump the primeruntil all of the water has beenremoved. When fuel emptiesfrom the valve, all the water hasbeen drained. Close the valvehand tight.

For van models, open theprimary fuel filter drain valve byturning it two to three turns.Allow the filter to drain until all ofthe water has been removed.Close the valve hand tight.Repeat this process for thesecondary fuel filter.

5. Remove the fuel-resistantcontainer and properly disposeof the contaminated fuel. To findout how to properly dispose ofcontaminated diesel fuel, see“What to Do With Used Oil”under Engine Oil Life System onpage 10‑10.

6. Install the fuel cap.

7. For pickup models, start theengine and let it run for afew minutes. If the engine stalls,the fuel system may need to beprimed. While draining the waterfrom the fuel filter, air may enterthe fuel system. If air hasentered the fuel system the fuelsystem will need to be primed.For van models, start the engineand let it run for a few minutes.

If the WATER IN FUEL message/warning light comes on again afterdriving a short distance or theengine runs rough or stalls, a largeamount of water has probably beenpumped into the fuel tank. The fueltank should be purged.



Fuel Priming

In order for the fuel system to workproperly, the fuel lines must be fullof fuel and contain no air. If airgets into the fuel lines, it will benecessary to prime the fuel lines toeliminate air before operating thevehicle and the fuel operatedheater (FOH).

If air is in the fuel lines. One of thefollowing may have happened:. The vehicle ran out of fuel.. The fuel filter was removed for

servicing or replacement.. The fuel lines were removed or

disconnected for servicing.. The fuel filter water drain valve

was opened while the enginewas running.

. The fuel operated heater (FOH)pump and FOH fuel lines wereremoved or disconnected forservicing.

If one or more of the above occur,it is very likely that air has enteredthe fuel system and priming the fuelsystem is needed before operatingthe vehicle. Air in the fuel linesdoes not harm the engine, the fueloperated heater (FOH), or thevehicle.

However, the engine and/or the fueloperated heater (FOH) may not beable to start until the fuel system isprimed and the air is removed.

To Prime the Vehicle(Pickup Models)

The vehicle is equipped with apriming pump which is part ofthe engine mounted fuel filter.The priming pump is hand operatedand is designed to bring fuel to theengine to eliminate any air in thefuel lines. To prime the engine:

1. Correct the condition thatcaused the loss of prime bymaking sure there is fuel inthe tank.

2. Make sure the fuel filter hasbeen installed and properlytightened.

3. Make sure the fuel lines areproperly connected and the fuelfilter is cool enough to touch.

4. Remove any dirt from the fuelfilter head and vent valve bywiping with a cloth.

5. Open the fuel filter ventvalve by turning the screwcounterclockwise several fullturns. The vent valve is locatedon top of the fuel filter housing.

6. Repeatedly push down on thefuel filter priming pump with thepalm of your hand. The pump islocated on top of the fuel filterhousing. Let the pump returnupward between pushes.

7. Operate the priming pump until asmall amount of fuel seeps fromthe vent valve. When fuel isseen, the filter is now full of fueland the system should beprimed.



8. Close the vent valve. Clean anyfuel that accumulated on the fuelfilter. Attempt to start the engine.The engine may start and stall.If this occurs, operate thepriming pump several timesin between starting attempts.Once the engine stays running,allow it to idle for a few minutes.Check the filter for leaks.

To Prime the Vehicle(Van Models)

The vehicle has an electricpriming pump. The priming pumpis operated electrically and isdesigned to bring fuel to the engineto eliminate any air in the fuel lines.To prime the engine:

1. Correct the condition thatcaused the loss of prime bymaking sure there is fuel inthe tank.

2. Turn the ignition key on for30 seconds. The fuel pump willbe operating and starting thepriming process. Do not startthe engine during the first30 seconds.

3. After completing the initial primein Step 2, turn the ignition off,then back to start, and crank theengine for 15 seconds.

4. If the engine does not start,repeat Steps 2 and 3 until theengine starts.

5. If the engine does not runafter repeating Steps 2 and 3three times, turn the ignition keyoff for 60 seconds, allowing theElectronic Control Module (ECM)to reset.

6. Repeat the above steps until theengine starts.

7. If the engine runs, but does notrun smoothly, increase theengine speed slightly bypressing the accelerator pedal.This will help to force out airthrough the system.

8. If the engine starts and runs butstalls again, turn the ignition keyoff for 60 seconds to reset theECM and repeat the stepsabove.

9. When the engine starts, let it idlefor a few minutes and check thefilters for any leaks.

To Prime the Fuel Operated Heater(FOH) Fuel Lines (Van Models)

See your dealer or qualifiedtechnician if the FOH fuel linesneed to be primed.



Running Out of Fuel

Pickup Models

If the engine stalls and you thinkthat you have run out of fuel, do thisto restart the engine:

{ WARNING

Diesel fuel is flammable. It couldstart a fire if it gets on hot engineparts. You could be burned. Donot let too much fuel flow from theair bleed valve, and wipe up anyspilled fuel with a cloth.

1. If parked on a level surface,add at least two gallons of fuel.However, if parked on a slope,up to five gallons of fuel mightneed to be added.

2. Follow the fuel primingprocedure earlier in this sectionto prime the fuel filter.

3. Turn the ignition key to STARTfor 10 to 15 seconds at a timeuntil the engine starts. If theengine tries to run, but does notrun smoothly, increase the rpm alittle using the accelerator pedal.This will help force air throughthe system.

4. Return to Step 2 if the enginestalls and will not restart.

Van Models

If the engine stalls and you thinkthat you may have run out of fuel,do this to restart the engine:

1. If parked on a level surface,add at least one gallon of fuel.However, if parked on a slope,up to five gallons of fuel mightneed to be added.

2. Follow the vehicle fuel systempriming procedure earlier in thissection to re‐prime the systemand re‐start the engine.

The check engine light may comeon if the vehicle has run out of fuel.This light may stay on for a fewdrive cycles after the condition iscorrected, but will eventually clearitself.

The fuel operated heater stopsautomatically when the fuel tankvolume is less or equal to10 percent of the total tank volume.If the vehicle runs out of fuel, theFOH fuel lines will not need to beprimed because they will still havefuel remaining.



Fuel Filter ReplacementPickup Models

If you want to change the fuel filteryourself, here's how to do it:

{ WARNING

Diesel fuel is flammable. It couldstart a fire if something ignites it,and you could be burned. Do notlet it get on hot engine parts, andkeep matches or other ignitionsources away.

First, drain any water from the filterfollowing the procedure for drainingwater listed previously.

The vehicle's engine must be offuntil the end of this procedure.

The fuel filter is located in theengine compartment on thepassenger side of the vehicle.

1. Apply the parking brake.Access the fuel filter through thepassenger side wheel houseopening. It is not necessary toremove all of the wheel linerfasteners.

2. Remove only the necessaryfasteners to allow the rear of thewheel liner to be loweredenough for fuel filter access.

3. Unplug the water sensor wireconnected to the fuel filter andunscrew the filter element.

4. Remove the filter element.If there is any dirt on the filtersealing surface, clean it off.Remove and reuse the watersensor float switch located onthe bottom of the fuel filter.

5. Install the new filter element.

6. Reinstall and tighten the filtercontainer and reconnect thewater sensor wire to the filter.

7. Reposition the wheel liner.

8. Install and tighten fasteners.

9. Use the fuel filter primingprocedure earlier in this sectionto prime the fuel filter.

10. Start the engine and let it idlefor five minutes. Check the fuelfilter and air bleed valve forleaks.

11. Reset the fuel filter monitor.See Fuel System Messages onpage 5‑12 for more information.



Van Models

If the fuel operated heater (FOH) isnot working, the FOH line requirespriming. See your dealer for service.See Fuel Operated Heater (FOH)(Van Models Only) on page 9‑10 formore information.

If you want to change the fuel filteryourself, here's how to do it:

{ WARNING

Diesel fuel is flammable. It couldstart a fire if something ignites it,and you could be burned. Do notlet it get on hot engine parts, andkeep matches or other ignitionsources away.

First, drain any water from the filterfollowing the procedure for drainingwater listed previously.

The vehicle's engine must be offuntil the end of this procedure.

The fuel filters are located on thedriver side frame rail in front of thefuel tank.

To minimize fuel siphoning fromthe fuel tank during fuel filterreplacement, be sure the fuel tankis less than 3/4 full.

Primary Filter (A)

1. Apply the parking brake.

2. Unplug the water sensor wireconnected to the fuel filter(lowest wire) and unscrew thefilter's cap.

3. Remove the filter element.If there is any dirt on the filtersealing surface, clean it off.

4. Install the new filter element.

5. Reinstall and tighten the filter'scap and reconnect the watersensor wire to the filter.



6. Follow the vehicle fuel systempriming procedure earlier in thissection to re‐prime the system.

7. Start the engine and let it idle forfive minutes.

Secondary Filter (B)

1. Apply the parking brake.

2. Unscrew the filter element.

3. Remove the filter element.If there is any dirt on the filtersealing surface, clean it off.Remove and reuse the waterdrain valve located at the bottomof the fuel filter.

4. Install and tighten the new filterelement.

5. Follow the vehicle fuel systempriming procedure earlier in thissection to re‐prime the system.

6. Start the vehicle and let it idle for5 minutes.

Filling the Tank

{ WARNING

Fuel vapor burns violently and afuel fire can cause bad injuries.To help avoid injuries to you andothers, read and follow all theinstructions on the fuel pumpisland. Turn off the engine whenrefueling. Do not smoke near fuelor when refueling the vehicle.Do not use cellular phones.Keep sparks, flames, andsmoking materials away from fuel.Do not leave the fuel pumpunattended when refueling thevehicle. This is against the law insome places. Do not re-enter thevehicle while pumping fuel. Keepchildren away from the fuel pump;never let children pump fuel.

Van Shown, Pickup Similar

The green fuel cap is located behinda hinged door on the driver side ofthe vehicle. On van models, theblue diesel exhaust fluid cap is alsobehind the fuel door. Do not removeboth caps at the same time.



For chassis-cab models, refuel thefront tank first, or in instances whenonly a partial fuel fill is desired.An automatic transfer mechanismwill maintain approximately equalfuel levels in both tanks, so noswitching is required by theoperator.

To remove the fuel cap, turn itslowly to the left (counterclockwise).

{ WARNING

Fuel can spray out on you if youopen the fuel cap too quickly.If you spill fuel and thensomething ignites it, you could bebadly burned. This spray canhappen if the tank is nearly full,and is more likely in hot weather.Open the fuel cap slowly and waitfor any hiss noise to stop. Thenunscrew the cap all the way.

Be careful not to spill diesel fuel.Do not top off or overfill your tank,and wait a few seconds after youhave finished pumping before youremove the nozzle. Clean fuelfrom painted surfaces as soon aspossible. See “Washing YourVehicle” in the Index of the ownermanual. When you put the fuel capback on, turn it to the right(clockwise) until you hear a clickingsound. Make sure you fully installthe cap.

{ WARNING

If a fire starts while you arerefueling, do not remove thenozzle. Shut off the flow of fuelby shutting off the pump or bynotifying the station attendant.Leave the area immediately.

Notice: If you need a new fuelcap, be sure to get the right type.Your dealer can get one for you.If you get the wrong type, it maynot fit properly.

Notice: If your vehicle has beenaccidentally filled with gasoline,do not run the engine or severeengine damage can occur.Contact your dealer to have thefuel system flushed.



Filling a Portable FuelContainer

{ WARNING

Never fill a portable fuel containerwhile it is in the vehicle. Staticelectricity discharge from thecontainer can ignite the fuelvapor. You can be badly burnedand the vehicle damaged if thisoccurs. To help avoid injury to youand others:

. Dispense fuel only intoapproved containers.

. Do not fill a container while itis inside a vehicle, in avehicle's trunk, pickup bed,or on any surface other thanthe ground.

(Continued)

WARNING (Continued)

. Bring the fill nozzle in contactwith the inside of the fillopening before operating thenozzle. Contact should bemaintained until the filling iscomplete.

. Do not smoke whilepumping fuel.

. Do not use a cellular phonewhile pumping fuel.

Towing

Trailer TowingWhen towing at high elevation onsteep uphill grades, consider thefollowing:

Engine coolant at higher elevationwill boil at a lower temperature thanat or near sea level. If the engine isturned off immediately after towingat high elevation on steep uphillgrades, the vehicle may showsigns similar to engine overheating.To avoid this, let the engine runwhile parked (preferably on levelground) with the transmission inP (Park) and the park brake appliedfor at least five minutes beforeturning the engine off. If theoverheat warning comes on, seeEngine Overheating on page 10‑26.



Use the following chart to determine how much the vehicle can weigh, based upon your vehicle model and options.

Vehicle Axle Ratio Max. Trailer Wt. GCWR**

C-2500 Pickup Models — 2WD*

Pickup Model Extended CabStandard Box1

3.73 7 938 kg (17,500 lbs) 11113 kg (24,500 lbs)

Pickup Model Crew CabStandard Box1

3.73 7 893 kg (17,400 lbs) 11113 kg (24,500 lbs)

Pickup Model Sierra Denali1 3.73 7 802 kg (17,200 lbs) 11113 kg (24,500 lbs)

Pickup Model Regular CabLong Box1

3.73 8 074 kg (17,800 lbs) 11113 kg (24,500 lbs)

Pickup Model Extended CabLong Box1

3.73 7 893 kg (17,400 lbs) 11113 kg (24,500 lbs)

Pickup Model Crew Cab Long Box1 3.73 7 802 kg (17,200 lbs) 11113 kg (24,500 lbs)

K-2500 Pickup Models — 4WD*

Pickup Model Extended CabStandard Box1

3.73 7 802 kg (17,200 lbs) 11113 kg (24,500 lbs)

Pickup Model Crew CabStandard Box1

3.73 7 575 kg (16,700 lbs) 11113 kg (24,500 lbs)

Pickup Model — Sierra Denali1 3.73 7 076 kg (15,600 lbs) 11113 kg (24,500 lbs)




Pickup Model Regular CabLong Box1

3.73 7 938 kg (17,500 lbs) 11113 kg (24,500 lbs)

Pickup Model Extended CabLong Box1

3.73 7 484 kg (16,500 lbs) 11113 kg (24,500 lbs)

Pickup Model Crew Cab Long Box1 3.73 7 076 kg (15,600 lbs) 11113 kg (24,500 lbs)

C-3500 Pickup Model Extended Cab — 2WD*

Single Rear Wheels1 3.73 7 847 kg (17,300 lbs) 11113 kg (24,500 lbs)

Dual Rear Wheels3 3.73 9 752 kg (21,500 lbs) 13 245 kg (29,200 lbs)

C-3500 Pickup Model Crew Cab Standard Box — 2WD*


Single Rear Wheels — SierraDenali1

3.73 7 756 kg (17,100 lbs) 11113 kg (24,500 lbs)

C-3500 Pickup Model Crew Cab Long Box — 2WD*



Dual Rear Wheels — Sierra Denali3 3.73 9 662 kg (21,300 lbs) 13 245 kg (29,200 lbs)




K-3500 Pickup Model Regular Cab — 4WD*



K-3500 Pickup Model Extended Cab — 4WD*



K-3500 Pickup Model Crew Cab Standard Box — 4WD*


Single Rear Wheels — SierraDenali1

3.73 7 620 kg (16,800 lbs) 11113 kg (24,500 lbs)

K-3500 Pickup Model Crew Cab Long Box — 4WD*



Dual Rear Wheels — Sierra Denali4 3.73 9 525 kg (21,000 lbs) 13 245 kg (29,200 lbs)




Vans Models — 2WD

G2500 Cargo Van Short Wheelbase 3.54 4 536 kg (10,000 lbs) 7 711 kg (17,000 lbs)

G2500 Cargo Van Long Wheelbase 3.54 4 536 kg (10,000 lbs) 7 711 kg (17,000 lbs)

G3500 Cargo Van Short Wheelbase 3.54 4 536 kg (10,000 lbs) 7 711 kg (17,000 lbs)

G3500 Cargo Van Long Wheelbase 3.54 4 536 kg (10,000 lbs) 8 391 kg (18,500 lbs)

G3500 Passenger Van ShortWheelbase

3.54 4 536 kg (9,900 lbs) 7 711 kg (17,000 lbs)

G3500 Passenger Van LongWheelbase 3.54 4 536 kg (9,700 lbs) 7 711 kg (17,000 lbs)

*Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 1 587 kg(3,500 lbs) maximum.**The Gross Combination Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicleand trailer including any passengers, cargo, equipment and conversions. The GCWR for the vehicle should not beexceeded.1Trailer rating limited to 5 897 kg (13,000 lbs) with ball hitch.2Trailer rating limited to 7 257 kg (16,000 lbs) with ball hitch.3Trailer rating limited to 7 484 kg (16,500 lbs) with ball hitch.4Trailer rating limited to 7 711 kg (17,000 lbs) with ball hitch.

See “Towing a Trailer” in the owner manual for more information.



Conversions andAdd-Ons

Power Take-Off (PTO)The power take‐off (PTO) is anupfitter integrated system thatallows the user to create anauxiliary power source for runningadd‐on equipment, such as saltspreaders, snow plows, winchesand lift buckets. The PTO systemcontrols engine speed to valueshigher than normal base idle,PTO load relay engagement andshutdown of the engine.

Primary PTO Operating Modes

PTO modes of operation include thefollowing:. Preset PTO Mode: (Stationary

operation only). Variable PTO Mode: (Stationary

and mobile operation)

The PTO stationary mode providesboth in‐cab and remote controls.The in‐cab controls are enabled asthe factory preset. The remotecontrols are disabled. This factorypreset configuration can beprogrammed to enable the remotecontrols, and/or disable the in‐cabPTO controls. See your dealer formore information.

PTO Sub – Modes

The primary PTO modes have thefollowing sub-modes:. Engine speed control. PTO load relay engagement/

disengagement. Remote engine start and

shutdown (Stationary vehicleoperation only)



PTO Enabling/DisablingConditions

Enabling Conditions –Stationary PTO

To engage stationary PTOoperation, the following conditionsmust be met:. The engine must be running.. The vehicle cannot be moving

and the parking brake mustbe set.

. The shift lever must be inP (Park) or N (Neutral).

. The brake pedal must not bepressed.

. The engine speed must beless than the maximum allowedPTO engage speed of 1500 rpm.The PTO engage speed can beadjusted by a service technician.

For in-cab PTO operation:

Press and release the 1 position onthe PTO switch. The PTO LED lightwill blink fast until the PTO loadbecomes engaged. The LED lightwill then be on steady. The −/SETand +/RES switch positions canthen be used to establish thedesired PTO operating speed.

For remote PTO operation:

Press and release the remotePTO arming switch, then withinfive seconds, move the PTO enableswitch from OFF to ON (open toclosed). The remote LED light willcome on when the PTO Load isengaged. The PTO remote SETswitch can then be used to establishthe desired PTO operating speed.

Additional information is availablein the service manual for thecorrect wiring configuration andprogramming of the remote PTOenable and set switches. Theseswitches are accessed through thePTO upfitter connector, locatedunder the passenger side door.

Enabling Conditions – Mobile PTO

To engage mobile PTO operation,the following conditions must be metprior to turning on PTO:. The engine must be running.. The vehicle speed must be less

than the PTO top vehicle speedlimit. The default setting is80 km/h (50 mph). This limitcan be adjusted by a servicetechnician.

. The shift lever may be in anyposition.



. The brake must be pressed andthen released. The brake mustthen remain released.

. Cruise control cannot be active.

. Engine speed must be less thanthe maximum allowed PTOengage speed of 1500 rpm.

. Press and release the 1 positionon the PTO switch. The PTOLED light will blink fast until thePTO load becomes engaged, atwhich point the LED light will beon steady. The −/SET and+/RES switch positions canthen be used to establish thedesired PTO operating speed.See Variable PTO Mode – PTOSwitch operation below.

DIC WARNING MESSAGES

One or more of the following DriverInformation Center (DIC) messagesmay appear on the instrument panelcluster if the PTO will not engage.The operator must take the actionindicated, then again press andrelease the 1 position of the PTOswitch.. PTO: SHIFT TO PARK OR

NEUTRAL (Stationary only). PTO: SET PARK BRAKE

(Stationary only). PTO: PRESS & RELEASE

BRAKE (Mobile only). PTO: RELEASE BRAKE. PTO: REDUCE VEHICLE

SPEED. PTO: REDUCE ENGINE SPEED. PTO: DISENGAGE CRUISE

CONTROL (Mobile only)

In addition to these messages, thePTO switch LED will indicate whenall conditions required to engagePTO have not been met. Whenenabling PTO, the LED will turn on,then off after one second. Undernormal operating conditions, thePTO LED will remain on throughoutthe PTO operating cycle.

PTO Disengage Conditions

To disengage the stationary ormobile PTO operation, do one of thefollowing:. Press the brake. PTO will

disengage immediately. ThePTO LED will blink slowly,indicating that the PTO setspeed is stored in memory.Pressing the +/RES switchposition will restore enginespeed to the stored PTO setspeed. PTO can also beprogrammed to reengage atPTO standby speed uponreleasing the brake pedal(mobile PTO only).



. Press and release the 0 on thePTO in‐cab switch. The enginespeed will return to normalengine idle. The PTO LED lightwill go off indicating the PTOload relay has been disengagedand PTO set speed has beencleared from memory.

. From the remote PTO controls,move the speed enable switch tothe off position. The engine willreturn to normal idle. The PTOload relay is disengaged. PTOmemory speed is also cleared.(Stationary PTO only)

. From the remote PTO controls,press the remote engineshutdown switch. PTO isdisengaged and the engine isshutdown simultaneously.(Stationary remote PTO only)

The mobile PTO mode will alsodisengage if the following conditionsare detected by the vehicleelectronics:. The PTO load becomes

disengaged. (See servicemanual)

. Vehicle speed exceeds80 km/h (50 mph).

. Engine speed exceeds themaximum allowed PTOoperating speed of 3100 rpm(factory setting 2100 rpm).

. The PTO control system willattempt to limit accelerator pedaland PTO switch input as thevehicle approaches the aboveoperational limits. There aresome vehicle conditions, suchas down hill acceleration,which may cause vehicle speedand/or engine speed limits tobe exceeded. Under theseconditions, PTO is disengaged.

The stationary PTO mode will alsodisengage if any of the followingconditions are detected by thevehicle electronics:. Movement of the vehicle.. The park brake is released.. The transmission is shifted

from P (Park) or N (Neutral) toD (Drive) or R (Reverse).

. The PTO load becomesdisengaged. (See servicemanual)



Preset PTO Mode

Preset PTO can only be usedwhen the vehicle is not moving.The engine speed is initially set to astand‐by engine speed (850 rpm)when the PTO in-cab 1 switchposition is pressed or, by pressingand releasing the remote armingswitch. Then within five seconds,assert the remote PTO enableswitch to on. This provides an initialstart-up engine speed to match theengagement of the PTO load.The PTO standby engine speedcan be reprogrammed to a higherspeed by your dealer.

Choose one of two factory presetsby pressing the PTO In-cab−/SET or +/RES switch positionsor the remote PTO SET switch.Speed 1 and Speed 2 areprogrammable by a servicetechnician from base engine idlerpm to max PTO operation speed(3100 rpm).. Speed 1: Pressing the −/SET

position of the PTO switchresults in a preset speed of1250 rpm.

. Speed 2: Pressing the +/RESposition of the PTO switchresults in a preset speed of1700 rpm.

Pressing the 0 switch position onthe PTO in-cab switch or moving theremote PTO enable switch to OFFresults in the return of the enginespeed back to normal idle. The PTOload relay is also disengaged.

Maximum PTO Operating Speed:During PTO operation, theaccelerator pedal can be pressed toadjust the engine speed. To protectthe PTO from over‐speed, the PTOsystem will disengage when theengine speed exceeds 2100 rpm.

The Stationary PTO Mode providesboth in‐cab and remote controls.The in‐cab controls are enabled asthe factory preset. The remotecontrols are disabled. This factorypreset configuration can also bereprogrammed to enable the remotecontrols, and disable the in-cabPTO controls (i.e., PTO switch,accelerator pedal). See your dealerfor more information.



Variable PTO Mode

In this mode, the vehicle can beprogrammed for stationary or mobileoperation.

The variable PTO mode controlsengine speed and PTO loadengagement is selected by eitherthe PTO in-cab or remote switches.Engine speed selection is variablebetween base engine idle speedand a maximum of 3100 rpm(factory setting 2100 rpm).

In the mobile PTO mode, thevehicle will operate at a vehiclespeed resulting from the currentPTO engine speed request andcurrent transmission gear rangeselected.

Vehicle speed stability is greatlyimproved by shifting into thetransmission manual mode becauseupshifts are limited. This reducesthe maximum vehicle speed whileallowing high engine speed

operation. Therefore, low vehiclespeed operation 16‐40 km/h(10‐25mph) and high PTOengine speed (1,500–2,000 rpm)can be achieved in the manualmode 1 and 2 transmission ranges.

PTO Switch Operation

The In-cab PTO Switch has fourpositions: R,9, −/SET, and +/RES.

R : This is the PTO switch Onposition.

To engage PTO, press and releasethe in‐cab 1 switch position or, pressand release the remote PTO armingswitch, then within five seconds,assert the remote enable switch toon. The vehicle will increase enginespeed to a factory preset enginespeed (800 rpm). This PTO stand‐byspeed is not intended to be anoperational PTO speed, but allowsthe engagement of the PTO at lowerinitial start-up rpm to match with theengagement of the PTO load relay.

The initial stand‐by speed can beadjusted by holding the acceleratorto the desired engine speed, thenpressing and releasing the 1 in‐cabPTO switch position. The currentengine speed will become the newstand‐by speed. This adjustmentcan only be done once at the initialengagement of PTO. The initialstand‐by speed adjustment must bebetween engine base idle speedand 1800 rpm (maximum PTOengage speed).

9 : This is the PTO switch Offposition.

Press and release the in‐cab9 switch position or assert theremote enable switch to off todisengage PTO. The engine speedwill be reduced to the base idlespeed and the PTO load relay willbe disengaged.



−/SET (SET/TAP-DOWN/COAST)

SET: Press and hold theaccelerator to obtain the desiredengine speed, then press andrelease the −/SET position of thePTO switch. The current enginespeed will be maintained. Thisaction can be repeated as desiredto a higher rpm value. The PTO setspeed cannot exceed 2100 rpm.

TAP-DOWN: Press and release the−/SET switch position on the PTOswitch to reduce the engine speedby increments of 100 rpm.

COAST: Press and hold the −/SETswitch position on the PTO switchto reduce the rpm by 200 rpm persecond until the desired enginespeed is reached or until the initialPTO standby speed is reached.

+/RES (RESUME/TAP-UP/ACCEL)

RESUME: When a PTO set speedhas been achieved, press andrelease the brake pedal. Enginespeed will reduce to basic idlespeed. The PTO LED will blinkslowly indicating the previous PTOset speed has been retained inmemory. Press and release the+/RES switch position to resume theprevious PTO set speed. The PTOset speed cannot exceed 2100 rpm.

TAP-UP: Press and release the+/RES position to increase theengine speed by increments of100 rpm.

ACCEL: Press and hold the+/RES position to increase the rpmby 200 rpm per second until thedesired engine speed is reachedor until the maximum allowablePTO set speed is reached.

Remote Engine Start Control

The vehicle’s PTO system allowsthe engine to be remotely startedwhile operating in the stationaryPTO mode. The vehicle wiringsystem provides for connections toa remote engine start arming switchand remote starting switch. Theseconnections are accessed throughthe upfitter connector.

The remote start function is initiatedby a sequence of switch actions,in addition to several vehicleconditions. The vehicle ignitionkey can be in any position orremoved from the ignition.



The following conditions must bemet before attempting to remotestart the engine:. The vehicle must be configured

for stationary PTO operation bya qualified dealer.

. The parking brake must be set.

. The transmission shift lever mustbe in P (Park).

. The vehicle hood must beclosed.

Once the above conditions are met,continue the remote start by doingthe following steps using the remotePTO controls:

1. Press and release the remotestart arming switch.

2. Within five seconds of releasingthe remote start arming switch,press and hold the engine startswitch for about two seconds(horn will sound) until the enginestarts.

3. Release the remote engine startswitch.

To enable normal PTO operationafter remotely starting the vehicle:

1. Press and release the remotestart arming switch.

2. Within five seconds of releasingthe remote start arming switch,the PTO remove enable switchmust be moved from OFF to ON.

3. The PTO system will raiseengine rpm to standby speedand engage the PTO load.Press the remote PTO −/SET or+/RES switch to elevate PTO tothe desired engine operatingspeed.

Remote Engine ShutdownControl

The vehicle’s PTO system allows forremote engine shutdown whileoperating in the stationary PTOmode. This feature has the followingfunctions:. Engine shutdown using the

operator remote switch:The vehicle wiring systemprovides remote engineshutdown switch connections,which is accessed through thePTO upfitter connector.

. Timed auto-engine shutdown:The timed auto-engineshutdown feature provides themeans to shut down the engineautomatically after a predefinedtime. PTO must be operationalfor this function to be active.



. Engine shutdown based oncritical engine conditions: Theengine will be shutdown whenPTO is operating if a criticalengine condition is detected bythe vehicle system (i.e., low oil,low oil pressure, hot engine, hottransmission, low fuel, dieselparticulate filter regeneration).If PTO operation is continuedwhen critical engine conditionsare present, a horn chirpwarning will occur after 2 to5 minutes. The engine will beshutdown 2minutes after thehorn warning. The operator canre-start the engine with theignition key. The above hornwarning and engine shutdownwill again occur if the criticalengine condition is still present.

Prolonged or Extended PTOOperation

While operating the vehicle instationary PTO mode, the DieselParticulate Filter (DPF) will continueto filter the exhaust and accumulatesoot. The engine control system,depending on the speed and loadbeing applied by the PTO, may notbe able to generate enough energyor adequate heat needed to clean orregenerate the DPF. Continuedoperation under conditions that donot allow effective regeneration orcleaning will eventually plug theDPF and result in reduced power.

The ENGINE POWER ISREDUCED Driver InformationCenter (DIC) message andMalfunction Indicator Lamp willbe displayed, and dealer servicewill be required to return the vehicleto normal, full power operation.To prevent this from occurring,frequently monitor the vehicle duringPTO operation. If the DIC messageis displayed during PTO operation,see Diesel Particulate Filter(Exhaust Filter) on page 9‑10 forinformation on how to clean orregenerate the DPF. Also see“Remote Engine Shutdown Control”earlier in this section.



Factory Preset Parameters

The following table lists the factory preset parameters. These may be altered by the service technician to configurethe various PTO features.

ProgrammableParameters

Factory Setting Minimum Value Maximum Value

PTO In-cab Control ENABLED DISABLED ENABLED

PTO Remote Control DISABLED DISABLED ENABLED

Type of Set SwitchOperation

MOMENTARY MOMENTARY LATCHING

Press ON then go toSet 1 Speed

DISABLED DISABLED ENABLED

Remote Engine Start DISABLED DISABLED ENABLED

Remote Engine Shutdown DISABLED DISABLED ENABLED

Load feedback DISABLED DISABLED ENABLED

Engage Relay DISABLED DISABLED ENABLED

Keep Relay engageduring braking






Action after brake isreleased

RETURN TO BASEIDLE RPM

RETURN TO BASEIDLE RPM

RETURN TOSTANDBY RPM

Auto Engine ShutdownTimer ENABLED DISABLED ENABLED

Eng. Shutdown due toFailure


Engine Shutdown warning DISABLED DISABLED ENABLED

Set Low Fuel level forEngine Shutdown

15% 0 25%

Engine Run Time WhilePTO is Active – Timer

7 Hours 4 minutes 7 hours

Min. PTO Engage Speed 500 RPM 500 RPM 1800 RPM

Max. PTO Engine Speed 1800 RPM 950 RPM 3100 RPM

PTO Standby RPM 850 RPM500 RPM Normal engineidle will override if higherthan Standby Speed

3100 RPM





PTO Set Speed 1 1250 RPM500 RPM PTO Set Speed 1cannot be set below PTO

Standby speed3100 RPM

PTO Set Speed 2 1700 RPM500 RPM PTO Set Speed 2cannot be set below PTO

Standby speed3100 RPM

Maximum Operating Speed 2100 RPM 500 RPM 3100 RPM

Tap Step 100 RPM 4 RPM 500 RPM

Ramp Rate 200 RPM 4 RPM 1000 RPM

Maximum Vehicle Speed 129 km/h (80 mph) 30 km/h (18 mph) 129 km/h (80 mph)

Minimum RemoteAccelerator Voltage

0.25 V 0.0 V 2.5 V

Maximum RemoteAccelerator Voltage

4.75 V 2.5 V 5.0 V





Wheel Speed Sensitivity HIGH LOW, MEDIUM, HIGH

Remote Set SwitchTransition to LowVoltage (<1.66 V)

SET_SPEED 1 STANDBY SPEED, SET SPEED_1 or SET SPEED_2

Remote Set SwitchTransition to Open State

(>1.66 V, <3.33 V)PTO_STANDBY STANDBY SPEED, SET SPEED_1 or SET SPEED_2

Remote Set SwitchTransition to HighVoltage (>3.33 V)

SET_SPEED 2 STANDBY SPEED, SET SPEED_1 or SET SPEED_2

If the PTO factory presetparameters do not match thesettings described above, then theymay have already been altered inorder to satisfy the requirements ofthe installed PTO system and bodyequipment.

See www.gmupfitter.com moreinformation on the installation ofwiring and programming for PTOaftermarket equipment.


Vehicle Care 10-1

Vehicle Care

General InformationAccessories andModifications . . . . . . . . . . . . . . . 10-2

Vehicle ChecksEngine CompartmentOverview . . . . . . . . . . . . . . . . . . . 10-4

Engine Oil . . . . . . . . . . . . . . . . . . . 10-7Engine Oil Life System . . . . . 10-10Automatic TransmissionFluid . . . . . . . . . . . . . . . . . . . . . . 10-11

Engine Air Cleaner/Filter . . . . 10-18Cooling System . . . . . . . . . . . . 10-21

Engine Coolant . . . . . . . . . . . . . 10-22Engine Overheating . . . . . . . . 10-26Starter Switch Check . . . . . . . 10-27Automatic Transmission ShiftLock Control FunctionCheck . . . . . . . . . . . . . . . . . . . . . 10-28

Ignition Transmission LockCheck . . . . . . . . . . . . . . . . . . . . . 10-28

Park Brake and P (Park)Mechanism Check . . . . . . . . 10-28

Electrical SystemEngine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . 10-29


10-2 Vehicle Care

General Information

Accessories andModificationsWhen non‐dealer accessories areadded to the vehicle, they can affectvehicle performance and safety,including such things as airbags,braking, stability, ride and handling,emissions systems, aerodynamics,durability, and electronic systemslike antilock brakes, traction control,and stability control. Some of theseaccessories could even causemalfunction or damage not coveredby the vehicle warranty.

Damage to vehicle componentsresulting from the installation or useof non‐GM certified parts, includingcontrol module modifications, is notcovered under the terms of thevehicle warranty and may affectremaining warranty coverage foraffected parts.

GM Accessories are designed tocomplement and function with othersystems on the vehicle. Your GMdealer can accessorize the vehicleusing genuine GM Accessories.When you go to your GM dealerand ask for GM Accessories, youwill know that GM-trained andsupported service technicians willperform the work using genuineGM Accessories.

See your vehicle's Warranty bookletfor more information.

Aftermarket EnginePerformance EnhancementProducts and Modifications

Some aftermarket engineperformance products andmodifications promise a way toincrease the horsepower and torquelevels of the vehicle's powertrain.You should be aware that theseproducts could have harmful effectson the performance and life of theengine, exhaust emission system,transmission, and drivetrain.The engines, transmissions, anddrivetrains have been designedand built to offer industry leadingdurability and performance in themost demanding applications.


Vehicle Care 10-3

Engine power enhancementproducts may enable the engine tooperate at horsepower and torquelevels that could damage, createfailure, or reduce the life of theengine, engine emission system,transmission, and drivetrain.Damage, failure, or reduced life ofthe engine, transmission, emissionsystem, drivetrain, or other vehiclecomponents caused by aftermarketengine performance enhancementproducts or modifications might notbe covered under the vehiclewarranty.


10-4 Vehicle Care

Vehicle Checks

Engine Compartment Overview

United States Pickup models Shown, Canada Similar


Vehicle Care 10-5

A. Coolant Surge Tank andPressure Cap

B. Remote Positive (+) Terminal

C. Battery

D. Engine Air Cleaner/Filter

E. Diesel Exhaust Fluid (DEF)Fill Tube

F. Engine Air Cleaner/FilterRestriction Indicator(If Equipped)

G. Engine Oil Dipstick

H. Engine Oil Fill Cap

I. Engine Fan (Out of View)

J. Automatic TransmissionDipstick

K. Power Steering Fluid Reservoir

L. Brake Fluid Reservoir

M. Auxiliary Battery

N. Underhood Fuse Block

O. Windshield Washer FluidReservoir

P. Remote Negative (-) Terminal


10-6 Vehicle Care

United States Van models Shown, Canada Similar


Vehicle Care 10-7

A. Battery

B. Coolant Surge Tank

C. Automatic TransmissionDipstick

D. Engine Fan (Out of View)

E. Engine Air Cleaner/Filter

F. Air Cleaner/Filter RestrictionIndicator

G. Power Steering Fluid Reservoir

H. Brake Fluid Reservoir

I. Windshield Washer FluidReservoir

Engine OilTo ensure proper engineperformance and long life, carefulattention must be paid to engine oil.Following these simple, butimportant steps will help protectyour investment:. Always use engine oil approved

to the proper specification and ofthe proper viscosity grade. See“Selecting the Right Engine Oil.”

. Check the engine oil levelregularly and maintain theproper oil level. See “CheckingEngine Oil” and “When to AddEngine Oil.”

. Change the engine oil at theappropriate time. See Engine OilLife System on page 10‑10.

. Always dispose of engine oilproperly. See “What to Do WithUsed Oil.”

Checking Engine Oil

It is a good idea to check the engineoil level at each fuel fill. In order toget an accurate reading, the oilmust be warm, at normal operatingtemperature, and the vehicle mustbe on level ground. The engine oildipstick handle is a yellow loop.See Engine Compartment Overviewon page 10‑4 for the location of theengine oil dipstick.

Obtaining an accurate oil levelreading is essential:

1. Turn off the engine and allow atleast five minutes for the oil todrain back into the oil pan. Witha cool engine, allow 30 minutes.Checking your oil level too soonafter engine shut off will notprovide an accurate oil levelreading.

2. Pull out the dipstick and clean itwith a paper towel or a cloth,then push it back in all the way.Remove it again, keeping thetip down.


10-8 Vehicle Care

When to Add Engine Oil

If the oil is below the cross‐hatchedarea at the tip of the dipstick, addone liter/quart of the recommendedoil and then recheck the level. See“Selecting the Right Engine Oil” foran explanation of what kind of oil touse. For engine oil crankcasecapacity, see Capacities andSpecifications on page 12‑2.

Notice: Do not add too much oil.Oil levels above or below theacceptable operating rangeshown on the dipstick are harmfulto the engine. If you find that youhave an oil level above theoperating range, i.e. the enginehas so much oil that the oil levelgets above the cross-hatched

area that shows the properoperating range, the engine couldbe damaged. You should drainout the excess oil or limit yourdriving of the vehicle and seek aservice professional to removethe excess amount of oil.

See Engine Compartment Overviewon page 10‑4 for the location of theengine oil fill cap.

Be sure to add enough oil to put thelevel somewhere in the properoperating range. Push the dipstickall the way back in when through.

Selecting the Right Engine Oil

Look for three things:. CJ-4

Oils designated as API CJ-4 arerequired for the vehicle. TheCJ-4 designation can appeareither alone or in combinationwith other American PetroleumInstitute (API) designations, suchas API CJ-4/SL. These lettersshow API levels of quality.

. SAE 15W-40

SAE 15W-40 is best for thevehicle. When it is very cold,below −18°C (0°F), useSAE 5W-40 to improve cold


Vehicle Care 10-9

starting. These numbers on theoil container show its viscosity,or thickness. Do not useother viscosity oils such asSAE 10W‐30, SAE 10W-40,or SAE 20W-50.

. American Petroleum Institute(API) symbol

This doughnut-shaped logo(symbol) is used on most oilcontainers to help you select thecorrect oil. It means that the oil hasbeen certified by the AmericanPetroleum Institute.

Look for this on the oil container,and use only those oils that displaythis logo.

Notice: Use only engine oils thathave the designation CJ-4 for thediesel engine. Failure to use therecommended oil can damage theDPF and result in engine damagenot covered by the vehiclewarranty.

Engine Oil Additives/EngineOil Flushes

Do not add anything to the oil.The recommended oils with theAPI service symbol are all that isneeded for good performance andengine protection.

Engine oil system flushes are notrecommended and could causeengine damage not covered by thevehicle warranty.

What to Do with Used Oil

Used engine oil contains certainelements that can be unhealthy foryour skin and could even causecancer. Do not let used oil stay onyour skin for very long. Clean yourskin and nails with soap and water,or a good hand cleaner. Wash orproperly dispose of clothing or ragscontaining used engine oil. See themanufacturer's warnings about theuse and disposal of oil products.

Used oil can be a threat to theenvironment. If you change yourown oil, be sure to drain all the oilfrom the filter before disposal. Neverdispose of oil by putting it in thetrash or pouring it on the ground,into sewers, or into streams orbodies of water. Recycle it by takingit to a place that collects used oil.


10-10 Vehicle Care

Engine Oil Life System

When to Change Engine Oil

This vehicle has a computer systemthat indicates when to change theengine oil and filter. This is basedon engine timing, engine load, andengine temperature, and not onmileage. Based on drivingconditions, the mileage at which anengine oil change is indicated canvary considerably. For the oil lifesystem to work properly, the systemmust be reset every time the oil ischanged.

When the system has calculatedthat oil life has been diminished,it indicates that an oil change isnecessary. A CHANGE ENGINEOIL SOON message comes on.Change the oil as soon as possiblewithin the next 1 000 km (600 miles).

It is possible that, if driving underthe best conditions, the oil lifesystem might indicate that an oilchange is not necessary for up to ayear. The engine oil and filter mustbe changed at least once a yearand, at this time, the system mustbe reset. Your dealer has trainedservice people who will perform thiswork and reset the system. It is alsoimportant to check the oil regularlyover the course of an oil draininterval and keep it at the properlevel.

If the system is ever resetaccidentally, the oil must bechanged at 5 000 km (3,000 miles)since the last oil change.Remember to reset the oil lifesystem whenever the oil is changed.

How to Reset the Engine OilLife System

Reset the system whenever theengine oil is changed so that thesystem can calculate the nextengine oil change.

To reset the Engine Oil Life Systemon van models:

1. Display the OIL LIFEREMAINING on the DIC.

2. Press and hold the SET/RESETbutton on the DIC for more thanfive seconds. The oil life willchange to 100%.

To reset the Engine Oil Life Systemon most pickup models:

1. Display the OIL LIFEREMAINING on the DIC. If thevehicle does not have DICbuttons, the vehicle must be inP (Park) to access this display.


Vehicle Care 10-11

2. Press and hold the SET/RESETbutton on the DIC, or the tripodometer reset stem if thevehicle does not have DICbuttons, for more thanfive seconds. The oil life willchange to 100%.

On all models, the Engine Oil LifeSystem can be reset as follows:

1. Turn the ignition to ON/RUN withthe engine off.

2. Fully press the accelerator pedalslowly three times withinfive seconds.

3. Display the OIL LIFEREMAINING on the DIC. If thedisplay shows 100%, the systemis reset.

4. Turn the key to LOCK/OFF.

If the CHANGE ENGINE OIL SOONmessage comes back on when thevehicle is started, the engine oil lifesystem has not reset. Repeat theprocedure.

Automatic TransmissionFluid

When to Check and Change(Pickup Models)

Change the fluid and filter at theintervals listed. See ScheduledMaintenance on page 11‑2.

And be sure to use the transmissionfluid listed in Recommended Fluidsand Lubricants on page 11‑8.

How to Check

Because this operation can be alittle difficult, the decision may bemade to have this done at thedealership service department.

If the decision is made to performthis operation, be sure to follow allthe instructions here, or a falsereading on the dipstick could result.

Notice: Too much or toolittle fluid can damage thetransmission. Too much canmean that some of the fluid couldcome out and fall on hot engineparts or exhaust system parts,starting a fire. Too little fluidcould cause the transmission tooverheat. Be sure to get anaccurate reading if checking thetransmission fluid.

Wait at least 30 minutes beforechecking the transmission fluid levelif the vehicle has been driven:. When outside temperatures are

above 32°C (90°F).. At high speed for quite a while.. In heavy traffic — especially in

hot weather.. While pulling a trailer.


10-12 Vehicle Care

Checking the Fluid Level

Prepare the vehicle as follows:. Park the vehicle on a level

place. Keep the engine running.. With the parking brake applied,

place the shift lever in P (Park).. With foot on the brake pedal,

run the engine for at leastone minute and shift to D (Drive).Then shift to N (Neutral) andthen R (Reverse) to fill thehydraulic system. Then, put theshift lever in P (Park).

. Allow the engine to run at idle(500 – 800 rpm). Slowly releasethe brake pedal.

Then, without shutting off theengine, follow these steps:

Cold Check Procedure

The purpose of the cold check is todetermine if the transmission hasenough fluid to be operated safelyuntil a hot check can be made.The fluid level rises as fluidtemperature increases. DO NOT fillabove the COLD CHECK band ifthe transmission fluid is belownormal operating temperatures.

1. Pull out the dipstick and wipe itwith a clean rag or paper towel.The transmission dipstick islocated near the center ofthe engine compartment.See Engine CompartmentOverview on page 10‑4 formore information on location.

2. Push it back in all the way, wait3 seconds and then pull it backout again.

3. Check the fluid level reading.Repeat the check procedure toverify the reading.

4. If the fluid level is within theCOLD CHECK band, thetransmission may be operateduntil the fluid is hot enough toperform a hot check. If the fluidlevel is not within the COLDCHECK band, add or drain fluidas necessary to bring the levelinto the middle of the COLDCHECK band.

5. Perform a hot check at the firstopportunity after the normaloperating temperature of 71°C(160°F) to 93°C (200°F) isreached.

6. If the fluid level is in theacceptable range, push thedipstick back in all the way.


Vehicle Care 10-13

Hot Check Procedure

The fluid must be hot to ensure anaccurate check. The fluid level risesas temperature increases.

1. Operate the transmission inD (Drive) until the normaloperating temperature of71°C (160°F) to 93°C (200°F)is reached.

2. Pull out the dipstick and wipe itwith a clean rag or paper towel.

3. Push it back in all the way, waitthree seconds and then pull itback out again. Repeat thecheck procedure to verify thereading.

4. Safe operating level is within theHOT RUN band on the dipstick.The width of the HOT RUN bandrepresents approximately1.0 liter (1.06 quart) of fluid atnormal operating temperature.

5. If the fluid level is not within theHOT RUN band, add or drainfluid as necessary to bring thefluid level to within the HOTRUN band.

6. If the fluid level is in theacceptable range, push thedipstick back in all the way.

Consistency of Readings

Always check the fluid level at leasttwice using the proceduresdescribed previously. Consistency isimportant to maintaining proper fluidlevel. If inconsistent readingspersist, check the transmissionbreather to be sure it is clean andunclogged. If readings are stillinconsistent, contact the dealer.


10-14 Vehicle Care

How to Add Fluid

In cold operation, Allisonrecommends using SyntheticTransmission Fluid approved toAllison Transmission specificationTES-295 in areas where theminimum ambient temperaturesare below −40°C (−40°F).

Refer to the MaintenanceSchedule to determine whatkind of transmission fluid to use.See Recommended Fluids andLubricants on page 11‑8.

Add fluid only after checking thetransmission fluid while it is hot.A cold check is used only as areference. If the fluid level is low,add only enough of the proper fluidto bring the level up to the HOT areafor a hot check. It doesn't take muchfluid, generally less than 0.5 L(1 pint). Do not overfill.

Notice: Use of the incorrectautomatic transmission fluid maydamage the vehicle, and thedamages may not be covered bythe vehicle warranty. Always usethe automatic transmission fluidlisted in Recommended Fluidsand Lubricants on page 11‑8.. After adding fluid, recheck the

fluid level as described under“How to Check.”

. When the correct fluid level isobtained, push the dipstick backin all the way.

When to Check and Change(Van Models)

Change the fluid and filter at theintervals listed. See ScheduledMaintenance on page 11‑2.

And be sure to use the transmissionfluid listed in “RecommendedFluids and Lubricants”. SeeRecommended Fluids andLubricants on page 11‑8 for moreinformation.

How to Check

Because this operation can be alittle difficult, the decision may bemade to have this done at thedealership service department.

If the decision is made to performthis operation, be sure to follow allthe instructions here, or a falsereading on the dipstick could result.


Vehicle Care 10-15

Notice: Too much or toolittle fluid can damage thetransmission. Too much canmean that some of the fluid couldcome out and fall on hot engineparts or exhaust system parts,starting a fire. Too little fluidcould cause the transmission tooverheat. Be sure to get anaccurate reading if checking thetransmission fluid.

Wait at least 30 minutes beforechecking the transmission fluid levelif the vehicle has been driven:. When outside temperatures are

above 32° C (90°F).. At high speed for quite a while.. In heavy traffic — especially in

hot weather.. While pulling a trailer.

To get the right reading, the fluidshould be at normal operatingtemperature, which is 82°C to 93°C(180°F to 200°F). Get the vehiclewarmed up by driving about24 km (15 miles) when outsidetemperatures are above 10°C(50°F). If it is colder than 10°C(50°F), drive the vehicle until theengine temperature gauge movesand then remains steady for10 minutes.

A cold check can be made afterthe vehicle has been sitting foreight hours or more with the engineoff, but this is used only as areference. Let the engine run atidle for five minutes if outsidetemperatures are 10°C (50°F) ormore. If it is colder than 10°C(50°F), the engine may have to idlelonger. Should the fluid level be lowduring this cold check, the fluid mustbe checked when hot before addingfluid. Checking the fluid hot will giveyou a more accurate reading of thefluid level.

Checking the Fluid Level

Prepare the vehicle as follows:. Park the vehicle on a level

place. Keep the engine running.. With the parking brake applied,

place the shift lever in P (Park).. With foot on the brake pedal,

move the shift lever througheach gear range, pausing forabout three seconds in eachrange. Then, position the shiftlever in P (Park).

. Let the engine run at idle forthree minutes or more.


10-16 Vehicle Care

Then, without shutting off theengine, follow these steps:

The transmission dipstick is locatednear the center of the enginecompartment and will be labeledwith the graphic shown.

See Engine Compartment Overviewon page 10‑4 for more informationon location.

1. Flip the handle up and then pullout the dipstick and wipe it witha clean rag or paper towel.

2. Push it back in all the way, wait3 seconds and then pull it backout again.

Check both sides of the dipstick,and read the lower level. Thefluid level must be in the COLDarea for a cold check or in theHOT or cross‐hatched area for ahot check. Be sure to keep thedipstick pointed down to get anaccurate reading.

3. If the fluid level is in theacceptable range, push thedipstick in all the way, then flipthe handle down to lock thedipstick in place.

What Transmission Fluidto Use (AllisonTransmission Only)

Cold Operation

When temperatures are very cold,the transmission will prevent certainoperations to protect againstdamage. The Chart below showsshift range availability based ontransmission oil temperatures:. All shift ranges available at

−25°C (−13°F) or above.. 2 (Second) and 3 (Third) shift

ranges only at −35°C (−31°F) to−25°C (−13°F).

. 2 (Second) shift range only at−35°C (−31°F) or lower.

Torque converter clutch operationwill also be prevented when air ortransmission oil temperatures arebelow certain levels.


Vehicle Care 10-17

Transmission shifting might befirmer with a cold transmission.This difference in shift quality isnormal.

A. For areas where ambienttemperatures stay above−40°C (−40°F), regulartransmission fluid can be used.See Recommended Fluids andLubricants on page 11‑8.

B. For areas where ambienttemperatures fall below−40°C (−40°F), synthetictransmission fluid approvedto Allison TransmissionSpecification should be used.See Recommended Fluids andLubricants on page 11‑8.The synthetic transmission fluidcan be used for all temperatureranges.

How to Add Fluid

Refer to the MaintenanceSchedule to determine what kindof transmission fluid to use.See Recommended Fluids andLubricants on page 11‑8.

Using a funnel, add fluid down thetransmission dipstick tube only afterchecking the transmission fluidwhile it is hot. A cold check is usedonly as a reference. If the fluid levelis low, add only enough of theproper fluid to bring the level up tothe HOT area for a hot check.

It does not take much fluid,generally less than 0.5 L (1 pint).Do not overfill.

Notice: Use of the incorrectautomatic transmission fluidmay damage the vehicle, and thedamages may not be covered bythe vehicle warranty. Always usethe automatic transmission fluidlisted in Recommended Fluidsand Lubricants on page 11‑8.. After adding fluid, recheck the

fluid level as described under“How to Check” earlier in thissection.

. When the correct fluid level isobtained, push the dipstick backin all the way. Then flip thehandle down to lock the dipstickin place.


10-18 Vehicle Care

Engine Air Cleaner/Filter

Pickup Models

The air cleaner/filter assembly mayhave an air cleaner/filter restrictionindicator that shows when theengine air cleaner/filter is dirty andneeds to be serviced.

The air cleaner/filter restrictionindicator is located on the aircleaner box.

When to Inspect

Inspect the air cleaner/filter every25 000 km (15,000 miles) andreplace the filter if necessary.

How to Inspect

When the restriction indicatorturns black, or is in the red/orange“change” zone, replace the filterand reset the restriction indicator.The air cleaner/filter assembly islocated on the front corner of theengine compartment on thepassenger's side of the vehicle.

To inspect and replace the filter andreset the restriction indicator:

A. Clamp

B. Cover Electrical Connector

C. Restriction Indicator

D. Cover Screws

1. Disconnect the harnessconnector from the air cleanercover connector (B).

2. Loosen the screw on theclamp (A) holding the air outletduct in place. Do not remove theclamp. Move the air duct aside.


Vehicle Care 10-19

3. Remove the two air cleanerhousing cover screws (D).

4. Raise the air cleaner housingcover and remove the aircleaner/filter from the air cleanerhousing. Care should be takento dislodge as little dirt aspossible.

5. Clean the filter sealing surfaceand the housing.

6. Install the new engine aircleaner/filter.

7. Lower the air cleaner housingcover and secure with thetwo screws.

8. Install the air duct and tightenthe screw on the clamp tosecure to the air cleanerhousing.

9. Install the harness electricalconnector.

10. Reset the air cleaner/filterrestriction indicator (C),if equipped, by pressing thetop button on the indicator.

See Scheduled Maintenance onpage 11‑2 to determine when toreplace the engine air cleaner/filter.

{ WARNING

Operating the engine with theair cleaner/filter off can cause youor others to be burned. The aircleaner not only cleans the air; ithelps to stop flames if the enginebackfires. Use caution whenworking on the engine and do notdrive with the air cleaner/filter off.

Notice: If the air cleaner/filter isoff, dirt can easily get into theengine, which could damage it.Always have the air cleaner/filterin place when you are driving.

Van Models

The air cleaner/filter assembly mayhave an air cleaner/filter restrictionindicator that shows when theengine air cleaner/filter is dirty andneeds to be serviced.

The air cleaner/filter restrictionindicator is located on the aircleaner resonator.


10-20 Vehicle Care

When to Inspect

See Scheduled Maintenance onpage 11‑2 for more information.

How to Inspect

When the restriction indicator is inthe red/orange “change” zone,replace the filter and reset therestriction indicator. The air cleaner/filter assembly is located at the frontof the engine compartment.

To inspect and replace the filter andreset the restriction indicator:

1. Loosen the screws on the coverof the housing and lift up thecover.

2. Remove the air cleaner/filterfrom the housing. Care shouldbe taken to dislodge as little dirtas possible.

3. Clean the filter sealing surfaceand the housing.

4. Install the new engine aircleaner/filter.

5. Reinstall the cover and tightenthe screws.

6. Reset the air cleaner/filterrestriction indicator, if equipped,by pressing the top button on theindicator.

See Scheduled Maintenance onpage 11‑2 to determine when toreplace the engine air cleaner/filter.

{ WARNING

Operating the engine with the aircleaner/filter off can cause youor others to be burned. The aircleaner not only cleans the air; ithelps to stop flames if the enginebackfires. Use caution whenworking on the engine and do notdrive with the air cleaner/filter off.

Notice: If the air cleaner/filter isoff, dirt can easily get into theengine, which could damage it.Always have the air cleaner/filterin place when you are driving.


Vehicle Care 10-21

Cooling SystemThe cooling system allows theengine to maintain the correctworking temperature.

Pickup Models

A. Coolant Surge Tank

B. Coolant Surge TankPressure Cap

C. Engine Cooling Fan(Out of View)

Van Models

A. Coolant Surge Tank

B. Coolant Surge TankPressure Cap

C. Engine Cooling Fan(Out of View)

{ WARNING

Heater and radiator hoses, andother engine parts, can be veryhot. Do not touch them. If you do,you can be burned.

Do not run the engine if there isa leak. If you run the engine, itcould lose all coolant. That couldcause an engine fire, and youcould be burned. Get any leakfixed before you drive the vehicle.

Notice: Using coolant otherthan DEX-COOL® can causepremature engine, heater core,or radiator corrosion. In addition,the engine coolant could requirechanging sooner, at 50 000 km(30,000miles) or 24months,whichever occurs first. Anyrepairs would not be covered bythe vehicle warranty. Always useDEX-COOL (silicate-free) coolantin the vehicle.


10-22 Vehicle Care

Engine CoolantThe cooling system in the vehicle isfilled with DEX-COOL® enginecoolant. This coolant is designed toremain in the vehicle for 5 years or240 000 km (150,000mi), whicheveroccurs first, if you add onlyDEX-COOL extended life coolant.

The following explains the coolingsystem and how to add coolantwhen it is low. If there is a problemwith engine overheating, see EngineOverheating on page 10‑26.

A 50/50 mixture of clean, drinkablewater and DEX-COOL coolant will:. Give freezing protection

down to −37°C (−34°F). Give boiling protection

up to 129°C (265°F)

. Protect against rust andcorrosion

. Help keep the proper enginetemperature

. Let the warning lights andgauges work as they should

Notice: Using coolant other thanDEX-COOL may cause prematureengine, heater core, radiator andfuel operated heater (van modelsonly) corrosion. In addition,the engine coolant may requirechanging sooner, at 50 000 km(30,000 mi) or 24 months,whichever occurs first. Anyrepairs would not be covered bythe vehicle warranty. Always useDEX-COOL (silicate-free) coolantin the vehicle.

What to Use

Use a 50/50 mixture of clean,drinkable water and DEX-COOLcoolant which will not damagealuminum parts. If using thismixture, nothing else needs to beadded.

{ WARNING

Adding only plain water or someother liquid to the cooling systemcan be dangerous. Plain waterand other liquids, can boil beforethe proper coolant mixture will.The vehicle's coolant warningsystem is set for the propercoolant mixture. With plain wateror the wrong mixture, the enginecould get too hot but you wouldnot get the overheat warning.The engine could catch fire andyou or others could be burned.Use a 50/50 mixture of clean,drinkable water and DEX-COOLcoolant.


Vehicle Care 10-23

Notice: If an improper coolantmixture is used, the engine couldoverheat and be badly damaged.The repair cost would not becovered by the vehicle warranty.Too much water in the mixturecan freeze and crack the engine,radiator, heater core, and otherparts.

If coolant has to be added morethan four times a year, have thedealer check the vehicle coolingsystem.

Notice: If you use extra inhibitorsand/or additives in your vehicle'scooling system, you coulddamage your vehicle. Use onlythe proper mixture of the enginecoolant listed in this manualfor the cooling system.See Recommended Fluidsand Lubricants on page 11‑8for more information.

Checking Coolant (Pickup Models)

The coolant surge tank is located inthe engine compartment on thepassenger side of the vehicle.See Engine Compartment Overviewon page 10‑4 for more informationon its location.

{ WARNING

Turning the surge tank pressurecap when the engine and radiatorare hot can allow steam andscalding liquids to blow out andburn you badly. Never turn thesurge tank pressure cap— evena little—when the engine andradiator are hot.

The vehicle must be on a levelsurface. When the engine is cold,the coolant level should be betweenthe MIN and MAX marks.


10-24 Vehicle Care

Checking Coolant (Van Models)

The surge tank is located near thecenter of the engine compartment.See Engine Compartment Overviewon page 10‑4 for more informationon its location.

{ WARNING

Turning the surge tank pressurecap when the engine and radiatorare hot can allow steam andscalding liquids to blow out andburn you badly. Never turn thesurge tank pressure cap— evena little—when the engine andradiator are hot.

The vehicle must be on a levelsurface. When the engine is cold,the coolant level should be at theCOLD FILL mark.

Adding Coolant (Pickup andVan Models)

If more coolant is needed, add theproper DEX-COOL coolant mixtureat the surge tank, but be careful notto spill it.

{ WARNING

You can be burned if you spillcoolant on hot engine parts.Coolant contains ethylene glycoland it will burn if the engine partsare hot enough. Do not spillcoolant on a hot engine.

Notice: This vehicle has aspecific coolant fill procedure.Failure to follow this procedurecould cause the engine tooverheat and be severelydamaged.


Vehicle Care 10-25

{ WARNING

Steam and scalding liquids from ahot cooling system can blow outand burn you badly. They areunder pressure, and if you turnthe coolant surge tank pressurecap— even a little— they cancome out at high speed. Neverturn the cap when the coolingsystem, including the coolantsurge tank pressure cap, is hot.Wait for the cooling system andcoolant surge tank pressure capto cool if you ever have to turnthe pressure cap.

If no coolant is visible in the surgetank, add coolant as follows:

1. Remove the coolant surge tankpressure cap when the coolingsystem, including the coolantsurge tank pressure cap andupper radiator hose, is nolonger hot.

Turn the pressure cap slowlycounterclockwise about one fullturn. If a hiss is heard, wait forthat to stop. A hiss means thereis still some pressure left.

2. Keep turning the pressure capslowly, and remove it.

3. Fill the coolant surge tank withthe proper mixture as follows:. To the MAX mark on the

pickup. To the FULL COLD mark

on the van

4. With the coolant surge tankpressure cap off, start theengine and let it run until theengine coolant temperaturegauge indicates approximately90°C (195°F).

By this time, the coolant levelinside the coolant surge tankmay be lower. If the level islower, add more of the propermixture to the coolant surge tankuntil the level reaches the properlevel.

5. Replace the pressure cap.Be sure the pressure cap ishand-tight and fully seated.

6. Verify coolant level after theengine is shut off and thecoolant is cold. If necessary,repeat coolant fill procedureSteps 1 through 6.

If the coolant level is still low afterhaving followed these steps twice,have the coolant system checked acertified technician at the dealer fora possible leak.

Notice: If the pressure cap is nottightly installed, coolant loss andpossible engine damage mayoccur. Be sure the cap is properlyand tightly secured.


10-26 Vehicle Care

Engine OverheatingThere is an engine coolanttemperature gauge on theinstrument panel cluster. See theowner manual for more information.

If Steam Is Coming from theEngine Compartment

{ WARNING

Steam from an overheated enginecan burn you badly, even if youjust open the hood. Stay awayfrom the engine if you see or hearsteam coming from it. Just turn itoff and get everyone away fromthe vehicle until it cools down.Wait until there is no sign ofsteam or coolant before you openthe hood.

(Continued)

WARNING (Continued)

If you keep driving when yourengine is overheated, the liquidsin it can catch fire. You or otherscould be badly burned. Stop yourengine if it overheats, and get outof the vehicle until the engineis cool.

Notice: If the engine catches firebecause of being driven with nocoolant, your vehicle can bebadly damaged. The costlyrepairs would not be covered bythe vehicle warranty.

If No Steam Is Coming fromthe Engine Compartment

The ENGINE OVERHEATEDSTOP ENGINE, or ENGINEOVERHEATED IDLE ENGINEDriver Information Center (DIC)message, along with a low coolantcondition can indicate a seriousproblem.

If there is an engine overheatwarning and the vehicle does nothave a low coolant condition, andno steam is heard or seen, theproblem may not be too serious.Sometimes the engine can get alittle too hot when the vehicle:. Climbs a long hill on a hot day. Stops after high-speed driving. Idles for long periods in traffic. Tows a trailer. See “Driving on

Grades” in the Index of thevehicle's owner manual


Vehicle Care 10-27

If the ENGINE OVERHEATEDSTOP ENGINE, or ENGINEOVERHEATED IDLE ENGINEDriver Information Center (DIC)message comes on with no sign ofsteam, try this for a minute or so:

1. In heavy traffic, let the engineidle in N (Neutral) while stopped.If it is safe to do so, pull offthe road, shift to P (Park) orN (Neutral) and let theengine idle.

2. Turn on the heater to full hot atthe highest fan speed and openthe window as necessary.

If the vehicle no longer has theoverheat warning, the vehicle canbe driven. Just to be safe, driveslower for about 10 minutes. If thewarning does not come back on,drive normally.

If the warning continues, pull over,stop, and park the vehicleright away.

If there is still no sign of steam andthe vehicle is equipped with anengine driven cooling fan, pushdown the accelerator until theengine speed is about twice as fastas normal idle speed for at leastfive minutes while the vehicle isparked. If the warning is still there,turn off the engine and get everyoneout of the vehicle until it cools down.

The decision may be made not to liftthe hood, but to get service helpright away.

Starter Switch Check

{ WARNING

When you are doing thisinspection, the vehicle couldmove suddenly. If the vehiclemoves, you or others could beinjured.

1. Before starting this check, besure there is enough roomaround the vehicle.

2. Firmly apply both the parkingbrake and the regular brake.See “Parking Brake” in theowner manual.

Do not use the acceleratorpedal, and be ready to turn offthe engine immediately if itstarts.

3. Try to start the engine in eachgear. The vehicle should startonly in P (Park) or N (Neutral).If the vehicle starts in any otherposition, contact your dealer forservice.


10-28 Vehicle Care

Automatic TransmissionShift Lock ControlFunction Check

{ WARNING

When you are doing thisinspection, the vehicle couldmove suddenly. If the vehiclemoves, you or others could beinjured.

1. Before starting this check,be sure there is enough roomaround the vehicle. It should beparked on a level surface.

2. Firmly apply the parking brake.See “Parking Brake” in theowner manual.

Be ready to apply the regularbrake immediately if the vehiclebegins to move.

3. With the engine off, turn theignition to ON/RUN, but do notstart the engine. Withoutapplying the regular brake,try to move the shift lever out ofP (Park) with normal effort. If theshift lever moves out of P (Park),contact your dealer for service.

Ignition TransmissionLock CheckWhile parked, and with the parkingbrake set, try to turn the ignition toLOCK/OFF in each shift leverposition.. The ignition should turn to

LOCK/OFF only when the shiftlever is in P (Park).

. The ignition key should comeout only in LOCK/OFF.

Contact your dealer if service isrequired.

Park Brake and P (Park)Mechanism Check

{ WARNING

When you are doing this check,the vehicle could begin to move.You or others could be injuredand property could be damaged.Make sure there is room in frontof the vehicle in case it begins toroll. Be ready to apply the regularbrake at once should the vehiclebegin to move.


Vehicle Care 10-29

Park on a fairly steep hill, with thevehicle facing downhill. Keepingyour foot on the regular brake,set the parking brake.. To check the parking brake's

holding ability: With the enginerunning and the transmission inN (Neutral), slowly remove footpressure from the regular brakepedal. Do this until the vehicle isheld by the parking brake only.

. To check the P (Park)mechanism's holding ability:With the engine running, shift toP (Park). Then release theparking brake followed by theregular brake.

Contact your dealer if service isrequired.

Electrical System

Engine Compartment Fuse Block

Pickup Models

The underhood fuse block is locatedin the engine compartment, on thedriver side of the vehicle. Lift thecover to access the fuse block.

For vans equipped with a Duramaxengine, see “Engine CompartmentFuse Block” in the vehicle ownermanual.


10-30 Vehicle Care

To remove fuses, hold the end ofthe fuse between your thumb andindex finger and pull straight out.

The vehicle may not be equippedwith all of the fuses and relaysshown.

Fuses Usage

1

Electronic StabilitySuspension Control,Automatic LevelControl Exhaust

2Left TrailerStop/Turn Lamp

3 Engine Controls

4Right TrailerStop/Turn Lamp

5 Front Washer

6 Fuel Heater

7Transmission ControlModule (Battery)

8Anti-lock BrakesSystem 2

Fuses Usage

9 Trailer Back-upLamps

10Left Low-BeamHeadlamp

11Engine ControlModule (Battery)

12Diesel ElectronicControl Module

13TransmissionIgnition 1

14Vehicle Back-upLamps

15Right Low-BeamHeadlamp

16Air ConditioningCompressor

17Electronic ControlModule/ThrottleControl

18 Fuel Pump

Fuses Usage

19 Integrated TrailerBrake Control

20 Headlamp Washer

21Rear WindshieldWasher

22 Trailer Park Lamps

23 Left Park Lamps

24 Right Park Lamps

25 Fog Lamps

26 Horn

27Right High-BeamHeadlamp

28Daytime RunningLamps

29Left High-BeamHeadlamp

30Daytime RunningLamp 2

31 Sunroof


Vehicle Care 10-31

Fuses Usage

32Key Ignition System,Theft DeterrentSystem

33 Windshield Wiper

34SEO B2 UpfitterUsage (Battery)

35Electric AdjustablePedals

36Climate Controls(Battery)

37Airbag System(Ignition)

38 Amplifier

39 Audio System

40Miscellaneous(Ignition), CruiseControl

41Tailgate Open/CloseAssist

Fuses Usage

42 Airbag System(Battery)

43Instrument PanelCluster

44 Power Take-Off

45

Auxiliary ClimateControl (Ignition),Compass andTemperature Mirror

46Center High-MountedStoplamp (CHMSL)

47 Rear Defogger

48 Heated Mirrors

49SEO B1 UpfitterUsage (Battery)

50Cigarette Lighter,Auxiliary Power Outlet

51

Automatic LevelControl CompressorRelay, SEO UpfitterUsage

Fuses Usage

52 Climate Controls(Ignition)

53Engine ControlModule, SecondaryFuel Pump (Ignition)

68 Fan

J-CaseFuses

Usage

54Automatic LevelControl Compressor

55Heavy Duty Anti-lockBrake System

56Anti-lock BrakeSystem 1

57 Starter

58Stud 2(Trailer Brakes)

59Left Bussed ElectricalCenter 1


10-32 Vehicle Care

J-CaseFuses

Usage

60Electric RunningBoards

61Heated WindshieldWasher System

62Four-Wheel DriveSystem

63Stud 1 (TrailerConnector BatteryPower)

64Mid-Bussed ElectricalCenter 1

65Climate ControlBlower

66Tailgate Open/CloseAssist

67Left Bussed ElectricalCenter 2

Relays Usage

FAN RLY Fan Relay

HDLPLO/HID

Low-Beam Headlamp

FOGLAMP Front Fog Lamps

A/CCMPRSR

Air ConditioningCompressor

STRTR Starter

PWR/TRN Powertrain

FUELPMP

Fuel Pump

PRKLAMP

Parking Lamps

REARDEFOG

Rear Defogger

RUN/CRNK

Switched Power


Service and Maintenance 11-1

Service andMaintenance

General InformationGeneral Information . . . . . . . . . . 11-1

Scheduled MaintenanceScheduled Maintenance . . . . . 11-2

Recommended Fluids,Lubricants, and PartsRecommended Fluids andLubricants . . . . . . . . . . . . . . . . . . 11-8

Maintenance ReplacementParts . . . . . . . . . . . . . . . . . . . . . . 11-11

Maintenance RecordsMaintenance Records . . . . . . 11-12

General InformationNotice: Maintenanceintervals, checks, inspections,recommended fluids, andlubricants are necessary to keepthis vehicle in good workingcondition. Damage caused byfailure to follow scheduledmaintenance might not becovered by the vehicle warranty.

Proper vehicle maintenance helpsto keep the vehicle in good workingcondition, improves fuel economy,and reduces vehicle emissions forbetter air quality.

Because of all the different wayspeople use vehicles, maintenanceneeds vary. The vehicle might needmore frequent checks and services.Please read the information underScheduled Maintenance. To keepthe vehicle in good condition, seeyour dealer.

The maintenance schedule is forvehicles that:. carry passengers and cargo

within recommended limits onthe Tire and Loading Informationlabel. See “Loading the Vehicle”in the owner manual.

. are driven on reasonable roadsurfaces within legal drivinglimits.

. are driven off-road in therecommended manner, pickupmodels only. See “Off‐RoadDriving” in the owner manual.

. use the recommended fuel.See Fuel for Diesel Engines onpage 9‑17.


11-2 Service and Maintenance

{ WARNING

Performing maintenance workon a vehicle can be dangerous.In trying to do some jobs, you canbe seriously injured. Do your ownmaintenance work only if youhave the required know-how andthe proper tools and equipmentfor the job. If you have any doubt,see your dealer to have aqualified technician do the work.See “Doing Your Own ServiceWork” in the owner manual.

At your General Motors dealer,you can be certain that you willreceive the highest level of serviceavailable. Your dealer has speciallytrained service technicians, usesgenuine GM replacement parts,as well as, up‐to‐date tools andequipment to ensure fast andaccurate diagnostics.

The proper replacement parts,fluids, and lubricants to use arelisted in Recommended Fluids andLubricants on page 11‑8 andMaintenance Replacement Parts onpage 11‑11. We recommend the useof genuine parts from your dealer.

Rotation of New Tires

To maintain ride, handling, andperformance of the vehicle, it isimportant that the first rotationservice for new tires be performed.Tires should be rotated every12 000 km/7,500 miles. See “TireInspection and Rotation” in theowner manual.

ScheduledMaintenanceWhen the Change Engine OilSoon Message Displays

Change engine oil and filter.See Engine Oil on page 10‑7.An Emission Control Service.

When the CHANGE ENGINE OILSOON message displays in theDriver Information Center (DIC),service is required for the vehicle assoon as possible, within the next1 000 km/600 miles. If driving underthe best conditions, the engine oillife system might not indicate theneed for vehicle service for morethan a year. The engine oil and filtermust be changed at least once ayear and the oil life system must bereset. Your dealer has trainedservice technicians who will performthis work and reset the system.



If the engine oil life system is resetaccidentally, service the vehiclewithin 5 000 km/3,000 miles sincethe last service. Reset the oil lifesystem whenever the oil is changed.See Engine Oil Life System onpage 10‑10.

Every Engine Oil Change. Change engine oil and filter.

Reset oil life system. SeeEngine Oil on page 10‑7 andEngine Oil Life System onpage 10‑10. An EmissionControl Service.

. Add diesel exhaust fluid.

. Engine coolant level check.See Engine Coolant onpage 10‑22.

. Engine cooling systeminspection. Visual inspection ofhoses, pipes, fittings, andclamps and replacement,if needed.

. Windshield washer fluid levelcheck. See “Washer Fluid” in theowner manual.

. Windshield wiper bladeinspection for wear, cracking,or contamination and windshieldand wiper blade cleaning,if contaminated. See “ExteriorCare” in the owner manual.Worn or damaged wiper bladereplacement. See “Wiper BladeReplacement” in the ownermanual.

. Tire inflation pressures check.See “Tire Pressure” in the ownermanual.

. Tire wear inspection. See “TireInspection” in the owner manual.

. Rotate tires if necessary.See “Tire Rotation” in theowner manual.

. Fluids visual leak check(or every 12 months, whicheveroccurs first). A leak in anysystem must be repaired andthe fluid level checked.

. Engine air cleaner filterinspection. See Engine AirCleaner/Filter on page 10‑18.

. Brake system inspection(or every 12 months, whicheveroccurs first).

. Steering and suspensioninspection. Visually inspectfront and rear suspension andsteering system for damaged,loose, or missing parts, signs ofwear or lack of lubrication.Inspect power steering linesand hoses for proper hook-up,binding, leaks, cracks, chafing,etc. Pickup models: Visuallycheck constant velocity joints,rubber boots, and axle sealsfor leaks.



. Lubricate the front suspension,steering linkage, rear drivelinecenter splines (van models),and parking brake cable guides.Control arm ball joints on pickupmodels require lubrication butshould not be lubricated unlesstheir temperature is −12°C(10°F) or higher, or they couldbe damaged. Vehicles usedunder severe commercialoperating conditions requirelubrication on a regular basisevery 5 000 km/3,000 miles.

. Body component lubrication.Lubricate all key lock cylinders,body door hinges, hood latchassembly, secondary latch,pivots, spring anchor, releasepawl, fuel door hinge, locks,latches, and any folding ormoving seat hardware. Pickupmodels: Lubricate tailgatehinges, tailgate linkage, tailgatehandle pivot points, and latchbolt. Van models: Lubricate hoodhinges and rear compartmenthinges. See Recommended

Fluids and Lubricants onpage 11‑8. More frequentlubrication may be requiredwhen the vehicle is exposed toa corrosive environment.Applying silicone grease onweatherstrips with a clean clothmakes them last longer, sealbetter, and not stick or squeak.

. Restraint system componentcheck. See “Safety SystemCheck” in the owner manual.

. Fuel system inspection fordamage or leaks.

. Exhaust system, including DPFpressure lines, and nearby heatshields inspection for loose ordamaged components. Check tobe sure that mud or dirt is notcaked on the exhaust system,especially in the area of thediesel particulate filter andtailpipe. Clean the area asneeded. See Diesel ParticulateFilter (Exhaust Filter) onpage 9‑10. At high mileages,

the DPF becomes loaded withash. This is normal. When theamount of ash loading is high,see your dealer for DPFcleaning or replacement.

. For vehicles with AllisonTransmission® only: At the firstengine oil change only, replaceexternal transmission filter.

. Vans with GVWR above 4 536 kg(10,000 lbs) and all pickups:Shields inspection for damageor looseness. Adjust or replaceas required. This is a NoiseEmission Control Service.Applicable to vehicles sold in theUnited States and recommendedfor vehicles sold in Canada.

. Air intake system check.Check the air intake systeminstallation to assure thatgaskets are properly sealedand that all hose connections,fasteners, and other componentsare tight. Also check to be surethat the air cleaner housing is



properly seated and the coverfits tightly. Tighten connectionsand fasteners or replacedamaged parts as necessary.This is a Noise Emission ControlService. Applicable to vehiclessold in the United States andrecommended for vehicles soldin Canada.

. Fuel filter service. An EmissionControl Service.

This vehicle has a CHANGEFUEL FILTER message in theDriver Information Center (DIC)to tell you when to replace thefuel filter. See Fuel SystemMessages on page 5‑12.Change the fuel filter a minimumof once every two years.The PERCENT FUEL FILTERLIFE REMAINING messagemay be used to decide if thefilter should be changed duringroutine vehicle service.

Additional Required Services

At the First 160 km/100 Miles,1 600 km/1,000 Miles, and10 000 km/6,000 Miles. For pickups with dual wheels:

Check dual wheel nut torque.For proper torque, see“Capacities and Specifications”in the owner manual.

Every 12 000 km/7,500Miles. Rotate tires. Tires should be

rotated every 12 000 km/7,500 miles. See “Tire Rotation”in the owner manual.

At Each Fuel Stop. Engine oil level check. See

Engine Oil on page 10‑7.. Engine coolant level check.

See Engine Coolant onpage 10‑22.

. Windshield washer fluid levelcheck. See “Washer Fluid” in theowner manual.

Once a Month. Tire inflation pressures check.

See “Tire Pressure” in the ownermanual.

. Tire wear inspection. See “TireInspection” in the owner manual.

. Sunroof track and sealinspection, if equipped. See“Sunroof” in the owner manual.

Once a Year. See “Starter Switch Check” in

the owner manual.. See “Automatic Transmission

Shift Lock Control FunctionCheck” in the owner manual.

. See “Ignition Transmission LockCheck” in the owner manual.

. See “Park Brake and P (Park)Mechanism Check” in the ownermanual.

. Accelerator pedal check fordamage, high effort, or binding.Replace if needed.

. Underbody flushing service.



First Engine Oil Change AfterEvery 40 000 km/25,000Miles. Pickup Models: Automatic

transmission fluid and externalfilter change (severe service)for vehicles mainly driven inheavy city traffic in hot weather,in hilly or mountainous terrain,when frequently towing atrailer, or used for taxi,police, or delivery service.See Automatic TransmissionFluid on page 10‑11.

. Four‐wheel drive pickup modelsonly: Transfer case fluid change(extreme duty service) forvehicles mainly driven off‐roadin four‐wheel drive. Vehiclesused for farming, mining,forestry, Department of NaturalResources (DNR), and snow

plowing occupations meet thisdefinition. Check vent hose attransfer case for kinks andproper installation. Check to besure vent hose is unobstructed,clear, and free of debris. Duringany maintenance, if a powerwasher is used to clean mudand dirt from the underbody,care should be taken to notdirectly spray the transfer caseoutput seals. High pressurewater can overcome the sealsand contaminate the transfercase fluid. Contaminated fluidwill decrease the life of thetransfer case and should bereplaced.

First Engine Oil Change AfterEvery 80 000 km/50,000Miles. Engine air cleaner filter

replacement. See Engine AirCleaner/Filter on page 10‑18.

. Pickup Models: Automatictransmission fluid and filterchange (normal service).See Automatic TransmissionFluid on page 10‑11.

. Van Models: Automatictransmission fluid and filterchange (severe service) forvehicles mainly driven inheavy city traffic in hot weather,in hilly or mountainous terrain,when frequently towing atrailer, or used for taxi,police, or delivery service.See Automatic TransmissionFluid on page 10‑11.



. Four‐wheel drive pickup modelsonly: Transfer case fluid change(severe service) for vehiclesmainly driven when frequentlytowing a trailer, or used for taxi,police, or delivery service.Check vent hose at transfercase for kinks and properinstallation. Check to be surevent hose is unobstructed, clear,and free of debris. During anymaintenance, if a power washeris used to clean mud and dirtfrom the underbody, care shouldbe taken to not directly spraythe transfer case output seals.High pressure water canovercome the seals andcontaminate the transfer casefluid. Contaminated fluid willdecrease the life of the transfercase and should be replaced.

First Engine Oil Change AfterEvery 160 000 km/100,000Miles. Van Models: Automatic

transmission fluid and filterchange (normal service).See Automatic TransmissionFluid on page 10‑11.

. Four‐wheel drive pickup modelsonly: Transfer case fluid change(normal service). Check venthose at transfer case forkinks and proper installation.Check to be sure vent hose isunobstructed, clear, and free ofdebris. During any maintenance,if a power washer is used toclean mud and dirt from theunderbody, care should be takento not directly spray the transfercase output seals. High pressurewater can overcome the sealsand contaminate the transfercase fluid. Contaminated fluidwill decrease the life of thetransfer case and should bereplaced.

First Engine Oil Change AfterEvery 240 000 km/150,000Miles. Engine cooling system drain,

flush, and refill (or everyfive years, whichever occursfirst). See Engine Coolant onpage 10‑22. An EmissionControl Service.

. Engine drive belts inspectionfor fraying, excessive cracks,or obvious damage (or every10 years, whichever occursfirst). Replace, if needed.



Recommended Fluids, Lubricants, and Parts

Recommended Fluids and LubricantsFluids and lubricants identified below by name, part number, or specification can be obtained from your dealer.

Usage Fluid/Lubricant

Engine Oil

Engine oils with the letters CJ-4 are required for your vehicle. The CJ-4designation can appear either alone or in combination with other AmericanPetroleum Institute (API) designations, such as API CJ-4/SL. These lettersshow API levels of quality. To determine the preferred viscosity for yourvehicle's diesel engine, see Engine Oil on page 10‑7.

Engine Coolant 50/50 mixture of clean, drinkable water and use only DEX-COOL Coolant.See Engine Coolant on page 10‑22.

Hydraulic Brake SystemDOT 3 Hydraulic Brake Fluid (GM Part No. U.S. 12377967,in Canada 89021320).

Diesel Exhaust AftertreatmentSystem

Diesel Exhaust Fluid (GM Part No. U.S. 88862659, in Canada 88862660)or diesel exhaust fluid that meets ISO 22241-1 or displays the API DieselExhaust Fluid Certification Mark.

Windshield Washer Optikleen® Washer Solvent.

Van Models: Parking BrakeCable Guides

Chassis Lubricant (GM Part No. U.S. 12377985, in Canada 88901242) orlubricant meeting requirements of NLGI #2, Category LB or GC-LB.

Power Steering SystemGM Power Steering Fluid (GM Part No. U.S. 89021184,in Canada 89021186).




Automatic Transmission

DEXRON®-VI Automatic Transmission Fluid.Allison Transmission Only: For areas where ambient temperatures arebelow -40°C (-40°F) use Synthetic Transmission Fluid approved toAllison Transmission specification TES‐295 (GM Part No. U.S. 12378515,in Canada 88900701).

Key Lock CylindersMulti-Purpose Lubricant, Superlube (GM Part No. U.S. 12346241,in Canada 10953474).

Pickup Models: Floor Shift LinkageLubriplate Lubricant Aerosol (GM Part No. U.S. 12346293,in Canada 992723) or lubricant meeting requirements of NLGI #2Category LB or GC-LB.

Chassis LubricationChassis Lubricant (GM Part No. U.S. 12377985, in Canada 88901242) orlubricant meeting requirements of NLGI #2, Category LB or GC-LB.

Van Models: Front Wheel BearingsWheel bearing lubricant meeting requirements of NLGI #2, Category GC orGC-LB (GM Part No. U.S. 1051344, in Canada 993037).

Front and Rear AxleSAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 89021677,in Canada 89021678).

Transfer Case DEXRON®-VI Automatic Transmission Fluid.

Van Models: One-Piece PropshaftSlip Yoke Spline, Two-PiecePropshaft Slip-in-Tube Spline

Spline Lubricant, Special Lubricant (GM Part No. U.S. 12345879,in Canada 10953511).




Pickup Models: Front AxlePropshaft Spline

Spline Lubricant, Special Lubricant (GM Part No. U.S. 12345879,in Canada 10953511).

Pickup Models: Rear DrivelineCenter Spline

Chassis Lubricant (GM Part No. U.S. 12377985, in Canada 88901242) orlubricant meeting requirements of NLGI #2, Category LB or GC-LB.

Hood HingesMulti-Purpose Lubricant, Superlube (GM Part No. U.S. 12346241,in Canada 10953474).

Pickup Models: Body Door HingePins, Tailgate Hinge and Linkage,Folding Seats, and Fuel Door Hinge

Multi-Purpose Lubricant, Superlube (GM Part No. U.S. 12346241,in Canada 10953474).

Pickup Models: Tailgate HandlePivot Points, Hinges, Latch Bolt,

and Linkage

Multi-Purpose Lubricant, Superlube (GM Part No. U.S. 12346241,in Canada 10953474).

Weatherstrip ConditioningWeatherstrip Lubricant (GM Part No. U.S. 3634770, in Canada 10953518)or Dielectric Silicone Grease (GM Part No. U.S. 12345579,in Canada 992887).

Weatherstrip SqueaksSynthetic Grease with Teflon, Superlube (GM Part No. U.S. 12371287,in Canada 10953437).



Maintenance Replacement PartsReplacement parts identified below by name, part number, or specification can be obtained from your dealer.

Part GM Part Number ACDelco Part Number

Engine Air Cleaner/Filter

Pickup Models 25945274 A3141C

Van Models 20815924 A3140C

Engine Fuel Filter

Pickup Models 12633243 TP3012

Van Models (Primary and Secondary Filter Kit) 19256348 TP3013*

Engine Oil Filter 88917036 PF2232

Use only the specified filters.*Racor service kit includes primary filter, secondary filter and o‐rings.



Maintenance RecordsAfter the scheduled services are performed, record the date, odometer reading, who performed the service, and thetype of services performed in the boxes provided. Retain all maintenance receipts.

Maintenance Record

DateOdometerReading

Serviced By Services Performed



Maintenance Record (cont'd)

Date OdometerReading



Technical Data 12-1

Technical Data

Vehicle DataCapacities andSpecifications . . . . . . . . . . . . . . 12-2

Engine Drive Belt Routing . . . 12-4


12-2 Technical Data

Vehicle Data

Capacities and SpecificationsThe following approximate capacities are given in metric and English conversions. See Recommended Fluids andLubricants on page 11‑8 for more information.

Application

Capacities

Metric English

Cooling System (Pickup Models) 27.0 L 28.5 qt

Cooling System (Van Models)

Front Heat or AC Only 20.0 L 21.2 qt

Front Heat or AC Plus Fuel Operated Heater (FOH) 20.9 L 22.1 qt

Front and Rear Heat or AC Only 21.5 L 22.7 qt

Front and Rear Heat or AC Plus Fuel OperatedHeater (FOH)

22.4 L 23.7 qt

Diesel Exhaust Fluid (DEF) Tank*

Pickup Models 20.1 L 5.3 gal

Van Models 20.1 L 5.3 gal


Technical Data 12-3

Application

Capacities

Metric English

Engine Oil With Filter 9.5 L 10.0 qt

Transmission Fluid (Pan Removal and Filter Replacement)

Auto 6-Speed Transmission Allison 7.0 L 7.4 qt

*Do not overfill the (DEF) tank. See Diesel Exhaust Fluid on page 9‑12.

All quantities are approximate. When adding, be sure to fill to the appropriate level, as recommended in thismanual. Recheck fluid level after filling.

Engine Specifications

Engine VIN Code Type

6.6L V8 Turbo Diesel (LGH Engine) L V8

6.6L V8 Turbo Diesel (LML Engine) 8 V8


12-4 Technical Data

Engine Drive Belt Routing


INDEX i-1

AAccessories andModifications . . . . . . . . . . . . . . . . . 10-2

Air Cleaner/Filter, Engine . . . . . 10-18Automatic TransmissionFluid . . . . . . . . . . . . . . . . . . . . . . . . .10-11

Automatic TransmissionShift Lock ControlFunction Check . . . . . . . . . . . . . 10-28

BBrakeExhaust (PickupModels Only) . . . . . . . . . . . . . . . .9-16

CCanadian Vehicle Owners . . . . . . . . . iiCapacities andSpecifications . . . . . . . . . . . . . . . . 12-2

CheckIgnitionTransmission Lock . . . . . . . . 10-28

Cluster, IP . . . . . . . . . . . . . . . . . . . . . . 5-2Cold Weather Operation . . . . . . . 9-27CoolantEngine . . . . . . . . . . . . . . . . . . . . . . 10-22

Cooling System . . . . . . . . . . . . . . . 10-21Engine Messages . . . . . . . . . . . . 5-11

CoversWinter . . . . . . . . . . . . . . . . . . . . . . . . . 9-5

DDieselStarting Your Engine . . . . . . . . . . . 9-1

Diesel Exhaust Fluid . . . . . . 1-5, 9-12Diesel Exhaust Fluid (DEF)Warning Light . . . . . . . . . . . . . . . . . 5-9

Diesel Exhaust FluidMessages . . . . . . . . . . . . . . . . . . . . 5-12

Diesel Particulate Filter . . . . . . . . 9-10Diesel Particulate FilterMessages . . . . . . . . . . . . . . . . . . . . 5-12

Driver InformationCenter (DIC) . . . . . . . . . . . . . . . . . 5-10

EElectrical SystemEngine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-29

EngineAir Cleaner/Filter . . . . . . . . . . . 10-18Compartment Overview . . . . . . .10-4Coolant . . . . . . . . . . . . . . . . . . . . . 10-22Cooling System . . . . . . . . . . . . . 10-21Cooling SystemMessages . . . . . . . . . . . . . . . . . . . 5-11

Drive Belt Routing . . . . . . . . . . . .12-4Oil Pressure Gauge . . . . . . . . . . . 5-5Overheating . . . . . . . . . . . . . . . . 10-26Power Messages . . . . . . . . . . . . . 5-11Starting Your Diesel . . . . . . . . . . . 9-1

Engine OilLife System . . . . . . . . . . . . . . . . . 10-10Messages . . . . . . . . . . . . . . . . . . . . 5-11

EnginesDiesel Fuel . . . . . . . . . . . . . . . . . . .9-17

Exhaust Brake(Pickup Models Only) . . . . . . . . 9-16


i-2 INDEX

FFilterDiesel Particulate . . . . . . . . . . . . .9-10Engine Air Cleaner . . . . . . . . . 10-18Replacement (Fuel) . . . . . . . . . . .9-33

FluidAutomatic Transmission . . . . .10-11Diesel Exhaust . . . . . . . . . . 1-5, 9-12

FuelCold Weather Operation . . . . . .9-27Diesel Engines . . . . . . . . . . . . . . .9-17Filling a Portable FuelContainer . . . . . . . . . . . . . . . . . . .9-37

Filling the Tank . . . . . . . . . . . . . . .9-35Filter Replacement . . . . . . . . . . .9-33Gauge . . . . . . . . . . . . . . . . . . . . . . . . . 5-4Operated Heater (FOH) . . . . . . .9-10Running Out of Fuel . . . . . . . . . .9-32System Messages . . . . . . . . . . . .5-12Water in Fuel . . . . . . . . . . . . . . . . .9-27What to Use in Canadaand Mexico . . . . . . . . . . . . . . . . . .9-22

What to Use in the U.S. . . . . . .9-18

Fuel for Diesel Engines . . . . . . . . 9-17FusesEngine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-29

GGaugesEngine Oil Pressure . . . . . . . . . . . 5-5Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4

General InformationService and Maintenance . . . . . 11-1

HHeaterFuel Operated . . . . . . . . . . . . . . . .9-10

IIgnition TransmissionLock Check . . . . . . . . . . . . . . . . . 10-28

Instrument Cluster . . . . . . . . . . . . . . 5-2Introduction . . . . . . . . . . . . . . . . . . . . . . . . ii

LLampsMalfunction Indicator . . . . . . . . . . 5-6

LightsWait to Start . . . . . . . . . . . . . . . . . . . 5-9

MMaintenanceRecords . . . . . . . . . . . . . . . . . . . . .11-12

Maintenance ScheduleRecommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . 11-8

Scheduled Maintenance . . . . . . 11-2Malfunction Indicator Lamp . . . . . 5-6MessagesDiesel Exhaust Fluid . . . . . . . . . .5-12Diesel Particulate Filter . . . . . . .5-12Engine Cooling System . . . . . . . 5-11Engine Oil . . . . . . . . . . . . . . . . . . . . 5-11Engine Power . . . . . . . . . . . . . . . . 5-11Fuel System . . . . . . . . . . . . . . . . . .5-12Service Vehicle . . . . . . . . . . . . . . .5-13


INDEX i-3

Messages (cont.)Starting the Vehicle . . . . . . . . . . .5-13Transmission . . . . . . . . . . . . . . . . .5-14Vehicle . . . . . . . . . . . . . . . . . . . . . . . 5-11Vehicle Speed . . . . . . . . . . . . . . . .5-14

OOilEngine . . . . . . . . . . . . . . . . . . . . . . . .10-7Engine Oil Life System . . . . . 10-10Engine Oil Pressure Gauge . . . . 5-5Messages . . . . . . . . . . . . . . . . . . . . 5-11

Overheating, Engine . . . . . . . . . . 10-26

PParkingBrake and P (Park)Mechanism Check . . . . . . . . 10-28

Over Things That Burn . . . . . . .9-10Power Take-Off (PTO) . . . . . . . . . 9-42

RRecommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . . 11-8

RecordsMaintenance . . . . . . . . . . . . . . . . .11-12

Replacement PartsMaintenance . . . . . . . . . . . . . . . . .11-11

Routing, Engine Drive Belt . . . . . 12-4Running Out of Fuel . . . . . . . . . . . 9-32

SScheduled Maintenance . . . . . . . 11-2ServiceAccessories andModifications . . . . . . . . . . . . . . . .10-2

Maintenance Records . . . . . . .11-12Maintenance, GeneralInformation . . . . . . . . . . . . . . . . . . 11-1

Vehicle Messages . . . . . . . . . . . .5-13Shift Lock Control FunctionCheck, AutomaticTransmission . . . . . . . . . . . . . . . . 10-28

Specifications andCapacities . . . . . . . . . . . . . . . . . . . . 12-2

Starter Switch Check . . . . . . . . . 10-27Starting the VehicleMesssages . . . . . . . . . . . . . . . . . . . 5-13

Starting Your Diesel Engine . . . . . 9-1SupplementUsing . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

TTowingTrailer . . . . . . . . . . . . . . . . . . . . . . . .9-37

Trailer Towing . . . . . . . . . . . . . . . . . 9-37TransmissionFluid, Automatic . . . . . . . . . . . . .10-11Messages . . . . . . . . . . . . . . . . . . . .5-14

UUsing this Supplement . . . . . . . . . . . . iii


i-4 INDEX

VVehicleCanadian Owners . . . . . . . . . . . . . . . iiMessages . . . . . . . . . . . . . . . . . . . . 5-11Personalization . . . . . . . . . . . . . . .5-15Speed Messages . . . . . . . . . . . . .5-14

WWait to Start Light . . . . . . . . . . . . . . 5-9Warning LightDiesel Exhaust Fluid (DEF) . . . . 5-9

Water in Fuel . . . . . . . . . . . . . . . . . . 9-27What Fuel to Use inCanada and Mexico . . . . . . . . . . 9-22

What Fuel to Use inthe U.S. . . . . . . . . . . . . . . . . . . . . . . 9-18

Winter Cover . . . . . . . . . . . . . . . . . . . 9-5

duramax diesel engine (lml/lgh) - 2011 black plate (1,1 ... · duramax diesel engine (lml/lgh) ......

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