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Service Bulletin

File in Section: -

Bulletin No.: 16-NA-135

Date: May, 2016

INFORMATION

Subject: 2017 GMC Acadia New Model Features

Attention: United States, Canada and Mexico. This Bulletin also applies to Export vehicles. ExportCountries Include: Afghanistan, Bahrain, Iraq, Jordan, Kuwait, Lebanon, Oman, Qatar,Saudi Arabia, UAE and Yemen.

Brand: Model:Model Year: VIN:

Engine: Transmission:From: To: From: To:

GMC Acadia 2017 2017 All All

Gasoline, 4Cylinder, L4,2.5L, DI,

DOHC, DCVCP,VVT —

RPO LCVGasoline, 6Cylinder, V6,3.6L, DI,

DOHC, VVT,GEN 2 —RPO LGX

Hydra-Matic™6T50,

Automatic, 6-Speed, GEN 3,

VAR 1 —RPO M2D

Hydra-Matic™6T70,

Automatic, 6-Speed, AWD,GEN 2 —RPO M7U

Hydra-Matic™6T70,

Automatic, 6-Speed, FWD,GEN 2 —RPO M7W

May, 2016 Bulletin No.: 16-NA-135

Overview

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Acadia Denali

Bulletin Purpose

This is a special bulletin to introduce the 2017 GMCAcadia. The purpose of this bulletin is to help theService Department Personnel become familiar withsome of the vehicle’s new features and to describesome of the action they will need to take to service thisvehicle.

Trim Levels

The 2017 Acadia is available in the following trimlevels: (some trim levels are not available in Canada)• Acadia SL FWD• Acadia SLE-1 FWD• Acadia SLE-2 AWD• Acadia SLT-1 FWD• Acadia SLT-2 AWD• Acadia All Terrain AWD, available on SLE-2

or SLT-1• Acadia Denali FWD• Acadia Denali AWD

Overview

The all-new 2017 Acadia is a reimagined crossoveraimed at the heart of the midsize segment, designed tooffer great versatility and refinement, with moreadvanced safety technologies. The new Acadia offersmore efficient powertrains, while continuing to offerthree rows of seating on most models. The premiumAcadia Denali returns, along with a new All Terrainmodel offering enhanced off-road capability. TheAcadia offers customers a midsize crossoverpositioned between the compact Terrain and full-sizeYukon. Depending on the model, it is available with five,six or seven passenger seating, while offering greatermaneuverability than the first-generation. The bodystructure incorporates press-hardened, high-strengthsteels, which allowed thinner components in someareas offering comparable or better crash performancethan conventional materials. They also help reduce thebase model curb weight by approximately 700 pounds(318 kg), compared to the current model. New splayedfront frame rails also contribute to crashworthiness.They flare outward to provide effective folding andcrushing performance during small overlap frontalcrash situations.

Bulletin No.: 16-NA-135 May, 2016

Vehicle Highlights

Some of the vehicle highlights are:A new 2.5L 4 cylinder engine is standard, and isbolstered by GMC’s first application of Engine AutoStop/Start technology, which enhances efficiency instop-and-go driving. The 2.5L is mated to theHydra-Matic™ 6T50 6-speed automatic transmission.A new available V6 3.6L engine is more powerful andefficient than the current model, while offering4,000 pounds (1,814 kg) estimated trailering capabilitywith the available towing package. The 3.6L is mated tothe Hydra-Matic™ 6T70 6-speed automatictransmission.Both of the engines feature direct injection (DI) andvariable valve timing (VVT), and both are mated toHydra-Matic™ 6-speed automatic transmissions andan electronically controlled drive mode selector.A split folding second row seat improves on the originalSmart Slide feature of the current model. It offersgreater flexibility, including the capability of thecurbside seat sliding and tilting forward even with aforward facing child seat in place. The driver sidesection tips and slides forward for easier access to thethird row.The 50/50-split, 2-passenger third row seat folds flat fora completely flat load floor behind the second row andwhen the second row is also folded, there’s 79 cubicfeet (2,237 liters) of cargo room. Levers at the rear ofthe vehicle make it easier to fold the second and thirdrow seats. All three rows offer USB charge ports forcompatible electronic devices.

The rear of the center console features a unique pullout storage drawer. It is accessible to rear seatpassengers and allows items such as electronicdevices and small toys to be stored out of sight forgreater security and reduced clutter.A new standard rear seat alert that can remind thedriver when an item may have been left in the secondand third row seats.HID lamps on the Denali and halogen projectors on theother models.Active safety features are designed to help makedrivers more aware of their surroundings and potentialcrash situations. They are available depending on themodel.An available Tow Vision Trailering system helps makehitching easier by employing a rear vision camera(RVC), with dynamic guidelines, to help line up theAcadia’s hitch with the trailer, as well as offering viewsof the trailer while driving.Available hands-free power liftgate.Capless refueling system.The Acadia has available phone integration technologythrough GMC’s available IntelliLink® system. It offerssupport for Apple® CarPlay™ and Android™ Auto andrequires a compatible smartphone. An availableOnStar® 4G LTE Wi-Fi hotspot provides a mobile hubfor drivers and passengers to stay connected. Thehotspot is ON whenever the vehicle is ON and comeswith a three-month/three-gigabyte data trial (UnitedStates and Canada).


Acadia All Terrain Model

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Acadia All TerrainThe new Acadia All Terrain model matches distinctivedesign elements with enhanced off-road-driving ability.At the heart of the Acadia All Terrain’s capability is the3.6L V6 matched with an advanced AWD system withActive Twin Clutch, which optimizes traction for everycondition it encounters. And while it is engineered foroptimal performance in wet, snowy and icy conditions,it also provides enhanced stability in dry conditions. Italso has a specific All Terrain mode in place of theOff-Road mode on the drive mode selector, whichworks with the model’s exclusive AWD system to offerenhanced hill-climb capability. All Terrain models aredistinguished from the rest of the Acadia lineup with abody-color grille surround, black chrome trim andunique wheels. Inside is exclusive 5 passenger seating(2+3), dynamic All Terrain interior accents and coveredstorage bins in the rear cargo floor in place of a thirdrow seat.Some additional features include:– Enhanced off-road/multi-terrain capabilities.– All Terrain option on Traction Mode Selector.– Hill Descent Control.– Premium performance on snow, mud or deep sand

surfaces.

Chassis and Driving Dynamics Features

Chassis and driving dynamics features include:• MacPherson strut front suspension.• Five-link rear suspension.• Rack mounted electric power steering system.• Four-wheel disc brakes with Duralife rotors.• Electronic park brake.• Available electronically controlled continuous

damping system (Denali).

New Available Safety Features

The following safety features are new and available onthe 2017 Acadia:• Lane Keep Assist.• Front Park Assist.• Front Pedestrian Braking• Forward Automatic Braking.• Lane Change Alert.• Safety Alert Seat.• Surround Vision.• IntelliBeam: Available IntelliBeam technology

automatically turns high-beam headlamps ON andOFF according to surrounding traffic conditions.


Brakes

This vehicle is equipped with a TRW EBC460 brakesystem. The electronic brake control module (EBCM)and the brake pressure modulator are servicedseparately. The brake pressure modulator uses a fourcircuit configuration to control hydraulic pressure toeach wheel independently.Depending on the vehicle options, the followingperformance enhancement systems are provided:• Antilock Brake System: When wheel slip is

detected during a brake application, an ABS eventoccurs. During ABS braking, hydraulic pressure inthe individual wheel circuits is controlled toprevent any wheel from slipping. A separatehydraulic line and specific solenoid valves areprovided for each wheel. The ABS can decrease,hold, or increase hydraulic pressure to eachwheel. The ABS does not, however, increasehydraulic pressure above the amount which istransmitted by the master cylinder during braking.

• Cornering Brake Control: Cornering brakecontrol is a slip control function that is intended toimprove the vehicle's lateral/yaw stability duringcombined braking and cornering situations. TheEBCM will reduce the brake pressure to the insidewheels by commanding the appropriate solenoidvalves ON and OFF.

• Dynamic Rear Proportioning: The dynamic rearproportioning is a control system that replaces themechanical proportioning valve. Under certaindriving conditions the electronic brake controlmodule will reduce the rear wheel brake pressureby commanding the appropriate solenoid valvesON and OFF.

• Hill Descent Control System: The hill descentcontrol system allows a smooth and controlled hilldescent in rough terrain without the driver needingto touch the brake pedal. The vehicle willautomatically decelerate to a low speed andremain at that speed while activated. Some noiseor vibration from the brake system may beapparent when the system is active. The descentcontrol system may be activated, if equipped, bypressing the button on the console. To activate,press the button when traveling at speeds lessthat 30 mph (48 km/h). To deactivate, press thebutton on the console, the brake pedal, or theaccelerator. Descent control enables the vehicleto descend using the ABS to control each wheel'sspeed. If the vehicle accelerates without driverinput, the system automatically applies the brakesto slow the vehicle down to the desired speed.

• Hill Hold Start Assist: The hill hold start assistallows the driver to launch the vehicle without aroll back while moving the foot from the brakepedal to the accelerator pedal. The EBCMcalculates the brake pressure, which is needed tohold the vehicle on an incline and locks thatpressure for a certain time by commanding theappropriate solenoid valves ON and OFF whenthe brake pedal is released. Hill hold start assist is

activated when the EBCM determines that thedriver wishes to move the vehicle up-hill, eitherbackwards or forwards.

• Hydraulic Brake Assist: The brake assistfunction is designed to support the driver inemergency braking situations. The EBCMreceives inputs from the brake pressure sensor.When the EBCM senses an emergency brakingsituation, the EBCM will actively increase thebrake pressure to a specific maximum.

• Intelligent Brake Assist: The intelligent brakeassist function is designed to provide limitedbraking to help prevent front and rear low speedcollisions. The EBCM receives inputs from thebrake pedal position sensor, wheel speedsensors, short range radar and ultrasonic sensorsto detect a collision. When the EBCM senses apossible collision, it will actively increase thehydraulic brake pressure to apply the brakes.

• Optimized Hydraulic Braking System: Withsome engines the EBCM monitors the vacuum inthe brake booster with a vacuum sensor andcontrols a brake booster vacuum pump dependingon vacuum sensor input. It also has a hydraulicbrake boost feature which supplements the brakesystem to maintain consistent brake performanceunder conditions of low brake booster vacuum.Low brake booster vacuum conditions can includeinitial start up after the vehicle has been parked forseveral hours, very frequent brake stops, or highaltitude driving. The hydraulic brake boost systemactivates only during a brake apply under lowvacuum conditions. In this case the EBCM willactively increase and control the hydraulic brakepressure by turning the pump motor ON and theappropriate solenoid valves ON and OFF. Whenhydraulic brake boost is active, a series of rapidpulsations is felt in the brake pedal.

• Stability Control: Electronic stability controlprovides added stability during aggressivemaneuvers. Yaw rate is the rate of rotation aboutthe vehicle's vertical axis. The stability control isactivated when the EBCM determines that thedesired yaw rate does not match the actual yawrate as measured by the yaw rate sensor. Thedifference between the desired yaw rate and theactual yaw rate is the yaw rate error, which is ameasurement of over steer or under steer. When ayaw rate error is detected, the EBCM attempts tocorrect the vehicle's yaw motion by applying brakepressure to one or more of the wheels. Theamount of brake pressure which is applied varies,depending on the correction required.

• Traction Control: When drive wheel slip is noted,the EBCM will enter traction control mode. First,the EBCM requests the engine control module(ECM) to reduce the amount of torque to the drivewheels via a serial data message. The ECMreduces torque to the drive wheels and reports theamount of delivered torque. If the engine torquereduction does not reduce drive wheel slip, theEBCM will actively apply the brakes on theslipping drive wheel. During traction controlbraking, hydraulic pressure in each drive wheelcircuit is controlled to prevent the drive wheels


from slipping. The EBCM commands the pumpmotor and appropriate solenoid valves ON andOFF to apply brake pressure to the slipping wheel.

• Trailer Brake Control System: A trailer brakecontrol system is used to control the amount oftrailer braking power that is made available totrailers with brakes that require a controlled outputelectrical signal for actuation. The trailer brakecontrol system determines the trailer brake type(Electric Brake or Electric Over Hydraulic Brake)automatically.

• Trailer Sway Control: The trailer sway controlwill detect any vehicle yaw instability, caused byan attached trailer. When instability is detected,the EBCM attempts to correct the vehicle's yawmotion by applying brake pressure to one or moreof the wheels. The engine torque may also bereduced, if it is necessary to slow down thevehicle.

Duralife Ferritic Nitro Carburized Rotors

The vehicle is equipped with Duralife ferritic nitrocarburized (FNC) brake rotors and low drag brakecalipers. Application of the FNC technology involves anadditional manufacturing process that heats the rotorsat 1,040°F (560°C) for up to 24 hours in a giant oven.Inside the nitrogen-rich atmosphere, nitrogen atomsbond to the surface of the steel rotor, hardening andstrengthening the rotor. This hardened layer allows therotor to wear slower and reduces rotor corrosion.

Engines

2.5L L4 Engine — RPO LCV

GM’s versatile and technologically advanced Ecotecengine family expands with a new, larger 2.5L variant. Itis based on a new generation of large-displacementfour-cylinder engines, which was designed for greaterefficiency. GM proprietary computational fluid dynamics(CFD) analysis techniques were used to develop anall-new combustion system with a higher compressionratio. The new combustion system features improvedknock resistance and higher flowing intake and exhaustports in the cylinder head which help increaseefficiency, power, and torque. The new Ecotec also hasincreased authority cam phasing to minimize anycompromise between efficiency, performance,emissions, and driveability. Like the current generationof technically advanced Ecotec engines, the 2.5L alsofeatures a high pressure direct injection fuel system,dual overhead camshafts with continuously variablevalve timing, electronic throttle control, and pistons withjet-spray oil cooling. When equipped with this engine,the vehicle has Active Grille Shutters.

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Shown is a typical view of the 2.5L L4 engine.

Engine Component Description and Operation

• Acoustic Intake Manifold Cover: The 2.5L usesa composite plastic lightweight intake manifold.But plastic conducts noise, so engineers wrappedthe intake with a clamshell-like isolating cover. Ithas a sound absorbing “blanket” on the inside thatsnugs against the intake to provide isolation, andthe cover has a visually clean outer layer, whichworks as a noise barrier.

• Cam Driven High Pressure Fuel Pump: A camdriven high pressure fuel pump provides the fuelpressure required of the direct injection (DI)system in the Ecotec 2.5L. The engine mountedfuel pump is augmented by a conventionalelectrically operated supply pump in the fuel tank.The fuel delivery system features a high-pressurestainless steel feed line and a pressure-regulatedfuel rail, without a conventional fuel return linefrom the engine to the tank. Fuel pressure variesfrom about 750 psi (5,171 kPa) at idle to 2,250 psi(15,513 kPa) at wide-open throttle.

• Camshaft Drive with Inverted Tooth Chain:Like the drive chain for the balance shafts, thecamshaft drive chain uses a premium, invertedtooth design that is significantly quieter than aroller type chain. As its name implies, an invertedtooth chain has teeth on its links – two-pin rollingpivot joints – that essentially wrap around the gearsprocket to take up virtually all the tension. Thisallows for smoother meshing of the chain links tothe sprocket teeth, the cause of most noise inchain drive systems. The chain to sprocket toothimpact is greatly reduced with the inverted toothdesign (also known as a silent chain drive), whichvirtually eliminates noise and enhances durability.

• Cylinder Block: The Ecotec 2.5L's sand-castcylinder block is a superior refinement of previousEcotec engine block castings. It is dimensionallysimilar with previous variants, while providing


excellent structural support, as well as enablinggreater control of noise, vibration and harshness.The main bearing bulkheads, which support thecrank bearing, as well as the cylinder bore walls,have been significantly strengthened to supportincreased engine loads. Also, refinements to theoil distribution system enable improved oil flowthroughout the engine; and an expansion of thecoolant jacket, along with the use of cast-in-placebore liners, allows more precise bore roundnessand improves the block’s ability to dissipate heat.

• Cylinder Head and Valves: The Ecotec 2.5L hasa 356T6 aluminum cylinder head that is cast withadvanced semi-permanent mold technology. Thisprovides excellent strength, reduced machiningand optimal port flow. There is no need for heattreatment to the casting, which reduces residualstress and, consequently, enhances the engine'sdurability. The cylinder head is designedspecifically for direct injection into eachcombustion chamber. This is accomplished bypositioning an injector under the intake port ofeach cylinder, so it protrudes into the chamber.The combustion chambers and ports areoptimized for direct injection and high port flow.The cylinder head includes premium valve seat,valve guide and valve materials. They wereselected for minimum wear while operating inmore severe conditions associated with directinjection. These premium materials, along with ahydraulic lash-adjusting lifter, ensure gooddurability without required lash adjustments. Thecylinder head also has integral cast oil passagesthat feed a set of internal oil control valves thatactivate cam phasers, enabling variable valvetiming.

• Direct Injection: Direct injection (DI) moves thepoint where fuel feeds into an engine closer to thepoint where it ignites, enabling greater combustionefficiency. It fosters a more complete burn of thefuel in the air-fuel mixture, and operates at a lowertemperature than conventional port injection. Thisallows the mixture to be leaner (less fuel and moreair), so less fuel is required to produce theequivalent horsepower of a conventional,port-injection fuel system. DI also delivers reducedemissions, particularly cold start emissions, byabout 25 percent. The fuel system operates atpressures as high as 2,250 psi (15,513 kPa)compared to about 60 psi (414 kPa) inconventional port-injected engines.

• DOHC with Continuously Variable ValveTiming: Overhead cams are the most direct,efficient means of operating the valves, while fourvalves per cylinder increase airflow in and out ofthe engine. This arrangement is integrated on theEcotec 2.5L's lightweight aluminum cylinder head.Both the intake and exhaust cams havehydraulically operated vane-type phasers that aremanaged by a solenoid and directed by the enginecontrol module (ECM). The phasers turn thecamshaft relative to the drive sprocket, allowingintake and exhaust valve timing to be adjustedindependently. Cam phasing changes the timingof valve operation as conditions such as rpm and

engine load vary. It allows an outstanding balanceof smooth torque delivery over a broad rpm range,high specific output and good specific fuelconsumption. Cam phasing also provides anothereffective tool for controlling exhaust emissions.Because it manages valve overlap at optimumlevels, it eliminates the need for a separateexhaust gas recirculation (EGR) system.

• Forged Steel Crankshaft: Engineers selected aforged steel crankshaft for the 2.5L because,along with its strength and durability, it is stifferthan a conventional cast iron crankshaft. Thatreduces noise and vibration at mid- and high-rpmlevels, enhancing the engine’s smoothness.

• Four-Wheel Drive Oil Pan: The oil filter for theLCV truck applications is now on the right handside of the oil pan. The oil pan has speciallyintegrated oil passages cast into the pan totransport oil to and from the oil filter. In addition,the oil pan features a deep rear sump allowing forclearance to the front axle.

• In-Pan Oil Pump Assembly: Another significantchange from previous Ecotec engines is therelocation of the oil pump assembly from the frontof the crankshaft to within the oil pan, where it isdriven by the second balance shaft. This reducesnoise from the front cover area, an aluminumintensive area that radiates noise and provides asmall drag torque to ensure quiet balance shaftgear operation. Also the oil-sump locationminimizes the potential for pump cavitation noise.

• Iron Main Bearing Cap Inserts: Iron inserts arecast into the 2.5L aluminum cylinder blockbedplate, enhancing the structure at the mainbearings, for greater smoothness and quietness.The bedplate provides stiffness to the bottom ofthe cylinder block and incorporates the mainbearing caps, the components used to secure thecrankshaft within the block. The iron insertmaterial ensures close main bearing tolerancesover a wide range of engine operatingtemperatures, for quieter engine lower end noise.

• Isolated Fuel Rail: The isolated fuel rail helpsachieve overall quietness. The fuel rail is a tubelike component that supplies gasoline to the DIinjectors. To reduce the noise associated with thisefficiency enhancing system, the injectors aresuspended and the fuel rail is attached to thecylinder head with rubber isolated, compressionlimiting mounting provisions.

• Relocated Balance Shafts: The 2.5L’s balanceshafts which are commonly used in four cylinderengines to reduce vibration are located in acassette in the oil pan. It’s a move from previousEcotec engines’ cylinder block-mounted shafts,which helps reduce noise through three keydesign features: a shorter, quieter drive chain,precision shaft-to-shaft reversing gears and lightdrag torque from driving the oil pump. The shortdrive chain eliminates the previous long, winding“bushed” chain that included driving the waterpump. It uses a premium inverted tooth chaindesign instead of a conventional roller-type chain,for quieter performance. The shaft-to-shaft


reversing gear set allows the drive gears of theshafts to mesh directly, eliminating the need for achain to “back drive” the second shaft, which mustrotate in the opposite direction of the first shaft.The second shaft also drives the oil pump,providing a light drag torque to preload thereversing gear teeth for smooth, rattle free andquiet operation.

• Structural Camshaft Cover: As a cast aluminumpart mounted on the very top of the engineassembly, the camshaft cover can be a significantsource of noise. That’s not the case with the 2.5L,due to a new, structural cover design that is stifferand mounts more rigidly to the engine. It featuresincreased ribbing and additional attachment boltsdown the center, all of which increase the cover’sstiffness to help push the engine’s soundfrequency above 2,000 hertz. It also enablesexcellent oil sealing for valvetrain oil controlpassages integrated within the cover.

• Structural Front Cover: Similar to the structuralcamshaft cover, the front cover which covers boththe camshaft drive system and balancer drivesystems, was designed with extra ribbing andsecured with extra fasteners, including a new rowof attachments down the middle of the cover. Likethe camshaft cover, the result is a stiffer, morerigid, quieter cover that contributes to reducedengine noise.

• Two Piece Oil Pan: When it came to the oil pan,engineers faced a conundrum: Aluminum providesstiffening structure to an engine, but it radiatesnoise. Stamped steel, on the other hand, radiatesless noise, but doesn’t offer the structural benefitsneeded for a stiff powertrain assembly. Theirsolution was to combine the materials to create aunique, two piece oil pan that features a stiffaluminum upper section to support the engine’sstructure, maintaining the Ecotec engine’ssignature full perimeter transmission mountingsurface and a stamped steel lower section toprovide greater overall sound performance.

• Two-Stage Thermostat: The coolantthermostat’s operating point is electronicallycontrolled to optimize engine temperatures duringdifferent phases of operation to enhance fuelefficiency. The engine control module monitorssensors and controls the thermostat based onmapping that takes into account the wide range ofengine operating conditions, includingtemperature and load. The thermostat openspartially at 194°F (90°C) and fully opens at 221°F(105°C).

• Two-Stage Variable Displacement Oil Pump:The variable-flow oiling system helps maximizefuel efficiency. Rather than the linear operation ofa conventional fixed-flow pump, it is accomplishedwith a crankshaft-driven oil pump that matches theoil supply to the engine load. The engine’svariable-flow pump changes its capacity based onthe engine’s demand for oil. This prevents usingenergy to pump oil that is not required for properengine operation. An engine oil cooler helpsmaintain optimum oil temperatures. It has a heatexchanger incorporated into the oil filter housing.

Coolant to the heat exchanger is provided by theengine’s coolant circuit. The design optimizes oilcooling with a minimal pressure loss. During coldstarting, the system also enables faster heating ofthe engine oil for an earlier reduction of internalengine friction.

• Vacuum Pump: A cam driven vacuum pumpensures the availability of vacuum under allconditions, especially under boost, when theengine produces the opposite of vacuum. Thepump is mounted at the rear of the cylinder headand is driven by the exhaust camshaft via aflexible coupling.

Engine Specifications

• Displacement: 2.5L (150 cubic inches)• Bore x Stroke : 3.46 inches (88.0 mm) x

3.976 inches (101.0 mm)• Compression Ratio: 11.3:1• Horsepower: 194 Horsepower (145 kW) @

6,300 RPM (SAE Certified)• Maximum Engine Speed: 6,850 RPM• Torque: 190 lb-ft (258 Nm) @ 4400 RPM (SAE

Certified)• Valves: 2 intake and 2 exhaust valves per

cylinder• Valve Lifters: Hydraulic roller finger follower• Recommended Fuel: Regular unleaded

3.6L V6 Engine — RPO LGX

The V6 3.6L engine ushers in new benchmarks forefficiency, refinement and durability. The clean-sheetengine redesign represents the fourth generation ofGM’s acclaimed DOHC V6 engine family andincorporates Active Fuel Management (AFM) alsoknown as cylinder deactivation technology to enhancefuel economy. The 3.6L also advances performanceand fuel economy by optimizing technologiesintroduced on previous generations, including directinjection (DI) and continuously variable valvetiming (VVT).


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Shown are typical views of the 3.6L V6 Engine.

Engine Component Description and Operation

• Active Fuel Management System: The ActiveFuel Management System (AFM) consists of thecamshafts, valves, the switching roller fingerfollowers (SRFF), also known as the valveswitching rocker arm, the dual feed hydraulic lashadjusters and the oil control valve (OCV) which isalso known as the valve rocker arm oil controlvalve.Depending on engine RPM, the ECM sends asignal to the OCV commanding it either ONor OFF.

With the AFM system ON, the OCV directs oil tothe dual feed hydraulic lash adjuster unlatchingthe switching roller finger followers creating zerolift and not allowing the valves to open oncylinders two and five. AFM is active at this time.With the AFM system OFF, the OCV is not activeand no oil is directed to the dual feed hydrauliclash adjuster. The switching roller finger followersoperate as normal rocker arms. AFM is inactive atthis time.

• Camshaft Drive System: The camshaft drivesystem consists of two timing drive chains drivenby the crankshaft which drives the respectivecylinder head's intake and exhaust camshaftposition actuators. Cushioned actuator chainsprockets have been added contributing to quieterengine operation. The timing drive chains usemoveable timing drive chain guides and ahydraulic-actuated tensioner. The tensionerminimizes timing drive chain noise and providesaccurate valve action by keeping slack out of thetiming drive chains and continuously adjusting fortiming drive chain wear. The tensionerincorporates a plunger that adjusts out with wearallowing only a minimal amount of backlash. Thetensioners are sealed to the head or block using arubber coated steel gasket. The gasket traps anadequate oil reserve to ensure quiet start-up.

• Camshaft Position Actuator System: Theengine incorporates a camshaft position actuatorfor each intake and exhaust camshaft. Camshaftphasing changes valve timing as engine operatingconditions vary. Dual camshaft phasing allows thefurther optimization of performance, fuel economyand emissions without compromising overallengine response and driveability. Variable valvetiming also contributes to a reduction in exhaustemissions. It optimizes exhaust and inlet valveoverlap and eliminates the need for an exhaustgas recirculation (EGR) system.The camshaft position actuator is a hydraulicvane-type actuator that changes the camshaftlobe timing relative to the camshaft drive sprocket.Engine oil is directed by a camshaft positionactuator oil control valve to the appropriatepassages in the camshaft position actuator. Oilacting on the vane in the camshaft positionactuator rotates the camshaft relative to thesprocket. At idle, both camshafts are at the defaultor "home" position. At this position, the exhaustcamshaft is fully advanced and the intake is fullyretarded to minimize valve overlap for smooth idle.In addition, this engine has intermediate parktechnology, which incorporates anintermediate-lock intake variable valve timing camphaser, allowing the cams to be parked at themost favorable position for cold starting. Underother engine operating conditions, the camshaftposition actuator is controlled by the enginecontrol module (ECM) to deliver optimal intake andexhaust valve timing for performance, driveabilityand fuel economy. The camshaft position actuatorincorporates an integral trigger wheel, which issensed by the camshaft position sensor mountedin the front cover, to accurately determine the


position of each camshaft. The exhaust camshaftposition actuator has a different internalconfiguration than the intake camshaft positionactuator since the exhaust camshaft positionactuator phases in the opposite direction relativeto the inlet camshaft position actuator.The camshaft position actuator oil controlvalve (OCV) directs oil from the oil feed in thehead to the appropriate camshaft position actuatoroil passages. There is one OCV for each camshaftposition actuator. The OCV is sealed and mountedto the front cover. The ported end of the OCV isinserted into the cylinder head with a sliding fit. Afilter screen protects each OCV oil port from anycontamination in the oil supply.

• Cooling System: This engine has a targetedcooling system which sends coolantsimultaneously to each water jacket in the headsand block. This new, parallel-flow designmaximizes heat extraction in the area of the upperdeck, intake and exhaust valve bridges in theheads and integrated exhaust manifold with aminimal amount of coolant. The result is moreeven and consistent cooling, which enhancesperformance, and faster engine warm up, whichimproves cold-start efficiency and reducesemissions.

• Connecting Rods and Pistons: The connectingrods are sinter-forged with a high copper contentand have press-in-place piston pin bushings. Theconnecting rods and rod cap are aligned by dowelpins retained in the cap. The cast aluminumpistons incorporate a polymer-coated skirt toreduce friction. The pistons are unique to the LGXboth for compression ratio and combustionefficiency. The piston uses two low tensioncompression rings and one multi-piece oilcontrol ring.

• Crankshaft: The crankshaft is a hardened,forged steel design with 4 main bearings.Crankshaft thrust is controlled by the upperportion of the number 3 main bearing. Thecrankshaft position reluctor wheel is pressed ontothe rear of the crankshaft in front of the rear mainjournal. A micro encapsulated adhesive is used onthe reluctor wheel to aid retention. This crankshaftis internally balanced.

• Cylinder Block: Stronger, stiffer aluminum blockwith increased structure in the bulkheads forsuperior rigidity.

• Cylinder Heads: The cylinder heads are a twopiece design consisting of a head and a camshaftcarrier which are cast aluminum with powderedmetal valve seat inserts and valve guides. The twopiece design allows for the Active FuelManagement (AFM) System. The cylinder headsalso feature integrated exhaust manifolds; theexhaust manifolds are incorporated into the headcasting. Two intake valves and two exhaust valvesare actuated by roller finger followers pivoting on astationary hydraulic lash adjuster (SHLA). In theLGX engine, the valves and seats are constructedwith specialized materials and coatings, and theexhaust valves are sodium filled for robustness.

The cylinder heads also feature a “high-tumble”port design, and are sealed with LGX specifichead gaskets. The head gaskets are also specificto the LH and RH sides.Separate exhaust and intake camshafts aresupported by bearings machined into thecamshaft carrier. The front camshaft bearing capis used as a thrust control surface for eachcamshaft. Each spark plug is shielded by a tubethat is pressed into the cylinder head. Each sparkplug ignition coil is also mounted through thespark plug tube. The LGX engine uses specificspark plugs and a different spark plug gap fromother HFV6 engines. The engine coolanttemperature (ECT) sensor is mounted in thethermostat housing near the flywheel end of theengine. With direct injection, the high pressureinjectors are located in machined bores below theintake ports. A stainless steel, high pressure fuelrail is attached to the intake side of the head. TheLGX engine has unique higher-flow injectors andfuel pump. The cylinder head has a larger bore forthe new larger diameter fuel pump follower thatoperates the higher-flow pump. The fuel injectorsare retained to the fuel rail in a new “twist-lock”retention scheme that does not require specialtools for service.

• Fuel Injectors and Spark Plugs: The injectorangle was changed to 24 degrees from22 degrees to reduce emissions and oil dilution. Asmaller 12 mm spark plug, down from 14mm,enables the plug to be located closer to the centerof the combustion chamber. This improves theflames propagation and increases light loadefficiency.

• Oiling System: The LGX engine contains adual-pressure control and variable-displacementvane pump that enhances efficiency by optimizingoil pressure as a function of engine speed. The oilpump is located beneath the cylinder block insidethe oil pan, contributing to the engines smootherand quieter operation. The oiling systemcomponents differ depending on the engine beingin a transverse or longitudinal orientation. TheLGX has unique oil pans depending onorientation, with the pans being separated into anupper (traditional aluminum) and lower (stampedsteel) pan. This configuration helps with noise andmass concerns. It also affords some serviceabilityimprovements through not needing to remove theentire upper pan for some service procedures; theprocedures can be performed through removingthe lower pan. The LGX oil pans contain oil levelswitches as do nearly all HFV6 applications. Theoil level switch is normally open and closes at oillevels above minimum requirements.

• Right and Left Bank Designation: Righthand (RH) and left hand (LH) designationthroughout the engine mechanical section areviewed from the rear, flywheel side, of the engineor from inside the vehicle. These banks are alsoreferred to as Bank 1 (RH) and Bank 2 (LH).

• Vacuum Pump: The engine utilizes a mechanicalvacuum pump to provide a vacuum source for thebraking system. The vacuum pump is integrated


into the oil pump assembly located in the oil pan.Both vacuum pump and oil pump are part of acommon assembly, referred to as a tandem pump.Neither pump is serviceable individually. If eitherthe oil pump or vacuum pump are defective,replace the entire tandem pump assembly.

Engine Specifications

• Displacement: 3.6 L (222 cubic inches)• Bore x Stroke : 3.74 inches (95 mm) x

3.377 inches (85.8 mm)• Compression Ratio: 10.2:1• Horsepower: 310 horsepower (231 kW) @

6,600 RPM (Estimate)• Maximum Engine Speed: 7,200 RPM• Torque: 271 lb-ft (367 Nm) @ 5,000 RPM

(Estimate)• Valves: 2 intake and 2 exhaust valves per

cylinder• Recommended Fuel: Regular unleaded

Engine Oil— dexos®

3512027

3511747

Ask for and use engine oils that meet the dexos®specification. Engine oils that have been approved byGM as meeting the dexos® specification are markedwith either of the dexos1® approved logos that areshown. For additional information, visit this GeneralMotors website: http://www.gmdexos.com

Viscosity Grade

2.5L L4 Engine: Use ACDelco® dexos®1 SAE 5W-20viscosity grade engine oil. SAE 0W-20 viscosity grademay be used as an alternative. An oil of this viscositygrade will provide easier cold starting for the engine atextremely low temperatures.

3.6L V6 Engine: Use ACDelco® dexos®1 SAE 5W-30viscosity grade engine oil. In an area of extreme cold,where the temperature falls below −20°F (−29°C) useSAE 0W-30 viscosity grade engine oil. An oil of thisviscosity grade will provide easier cold starting for theengine at extremely low temperatures.

Engine Oil Life System

The vehicle features GM’s engine oil life system, whichbetter protects engines by recommending oil changesbased on a computer software algorithm using actualengine operating conditions and can save the vehicleowner money by avoiding unnecessary oil changes.

Engine Auto Stop/Start— 2.5L

A fuel-saving Engine Auto Stop/Start system has beenintegrated with the 2.5L engine. While driving, when thebrake pedal is applied and the vehicle is at a completestop, the Engine Auto Stop/Start system may turn theengine OFF, depending on operating conditions. Whenthe engine is OFF, the tachometer will read AUTOSTOP. Upon releasing the brake pedal or applying theaccelerator pedal, the engine will restart. After parkingthe vehicle and turning the engine OFF, the tachometerwill read OFF.An upgraded starter motor and advanced batterytechnology support the increased number of enginestarts. The starter motor has a high performance


electric motor and stronger pinion engagementmechanism. The starter motor has also beenre-designed to reduce the noise on startup. Advancedbattery technology ensures it can handle frequentcharge and discharge cycles. An intelligent batterysensor module monitors the state of charge and healthof the battery. Battery state of charge and health areused by the ECM to determine if the Stop/Start functionmay be performed.The engine may remain running or restart if:• A minimum vehicle speed is not reached.• The engine or transmission is not at the required

operating temperature.• The outside (ambient) temperature is not in the

required operating range.• The shift lever is in any gear other than D (Drive).• The battery charge is low.• The current settings for the climate control (HVAC)

or defog system have not been reached.• The AUTO STOP time is greater than 2 minutes.

Instrument Panel Cluster— DriverInformation Center

Instrument Panel Cluster - Base

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The instrument panel cluster (IPC) - Base, comesstandard with an array of gauges. The IPC provides thedriver with important vehicle information at a glance.The base cluster consists of a speedometer,tachometer, temperature gauge, oil pressure warninglight, battery voltage warning light and fuel gauge withthe DIC in the lower middle.

Instrument Panel Cluster - Midlevel

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The IPC - Midlevel, comes standard with an array ofgauges. The IPC provides the driver with importantvehicle information at a glance. The midlevel clusterconsists of a speedometer, tachometer, temperaturegauge, oil pressure warning light, battery voltagewarning light and fuel gauge with the DIC in the lowermiddle.

Instrument Panel Cluster - Uplevel (EnglishStandard Theme)

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4495817

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The Uplevel cluster consists of a digital speedometer,tachometer, temperature gauge, oil pressure gauge,battery voltage gauge and fuel gauge with aninteractive display area in the center of the instrumentcluster. There are other lamps and indicators near eachof the turn signal indicator lamps and at the bottom ofthe IPC.

OnStar® with 4G LTE and Wi-Fi (NotAvailable in All Exported Countries)

With OnStar® 4G LTE and Wi-Fi, up to seven devicessuch as smartphones, tablets and laptops can beconnected to high-speed Internet through the vehicle’sbuilt-in Wi-Fi hotspot.To retrieve the SSID and password for the hotspot,press the OnStar® Voice Command button on theoverhead console or rearview mirror, wait for theprompt, and then say “Wi-Fi Settings.” The informationwill be displayed on the screen.

The powerful OnStar® connection also enablesimproved access to existing OnStar® safety andsecurity services, including the ability to transmit voiceand data simultaneously. That means OnStar®advisors can run a diagnostic check without everleaving the call, making customer interactions quickerand more seamless. It’s the most comprehensivein-vehicle safety and connectivity system available.For assistance, press the blue OnStar® button or call1-888-4-ONSTAR (1-888-466-7827).

Radio with IntelliLink®

Radio — 7 Inch Diagonal Color Touch

Offered as the base radio, the 7 inch (178 mm) diagonalcolor touch radio with IntelliLink® capacitive touchdisplay make the drive an inspired experience. Apple®CarPlay™ and Android™ Auto compatibility withcompatible smartphone.This radio features:• Simple, affordable method of connectivity.• Relies on customer’s brought-in media.• Physical buttons and knobs.• Icon based user interface.• Wi-Fi signal type, strength display and connection

settings.

Radio — 8 Inch Diagonal Color Touch

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The 8 inch (203 mm) diagonal color touch radio withIntelliLink® capacitive touch display make the drive aninspired experience. Apple® CarPlay™ and Android™Auto compatibility with compatible smartphone.This radio features:• Blend of embedded and customer brought-in

media functionality.• Fast accurate voice recognition including

partial name.• Gesture recognition.• Customizable options.


• Wi-Fi signal type, strength display and connectionsettings.

• Available navigation. (Not all countries).

Bluetooth® SystemBefore using a Bluetooth® enabled device in thevehicle, it must be paired with the in-vehicle Bluetooth®system. The pairing process is disabled when thevehicle is moving. Not all devices will support allfunctions. Bluetooth® streaming audio is available withthe IntelliLink® system.

Portable Audio Devices

A USB port is located at the front of the center console.An Apple® iPod®, iPhone®, MP3 Player, a USB flashdrive or a USB mass storage device can be connectedto the USB port. Compatible devices connected to theUSB port can be controlled by the audio system. Not alldevices may be supported. Use the audio controls andaudio steering wheel controls to access variousfunctions.

Safety— Airbag System

Airbag Readiness Light

This light illuminates and stays ON if there is anelectrical problem with the airbag system. The systemcheck includes the airbag sensors, passenger sensingsystem, the pretensioners, the airbag modules, thewiring, and the crash sensing and diagnostic module(SDM). The airbag readiness light turns ON for severalseconds when the vehicle is started. If the light doesnot turn ON and then OFF, have it repairedimmediately.

Airbag Locations

All vehicle airbags have the word AIRBAG on the trimor on a label near the deployment opening. The airbagsare located in the following positions:– A frontal airbag for the driver.– A frontal airbag for the front outboard passenger.– A knee airbag for the driver.– A front center airbag for the driver and front outboard

passenger.– Seat-mounted side impact airbag for the driver.– Seat-mounted side impact airbag for the front

outboard passenger.– A roof-rail airbag for the driver and for the second

and third row passengers seated directly behind thedriver.

– A roof-rail airbag for the front outboard passengerand the second and third row passengers seateddirectly behind the front outboard passenger.

Safety— Driving/Parking AssistanceSystems

If equipped, these systems may help the driver to parkand/or to avoid other vehicles, objects, pedestrians andanimals.• Active Tow: This feature displays a single,

centered guideline on the camera display to assistwith aligning a vehicle’s hitch bar with a trailercoupler. Select the trailer guidance line button,then align the trailer guidance line over the trailercoupler. Continuously steer the vehicle to keep theguidance line centered on the coupler whenbacking. RVC Parking Assist overlays will notdisplay when the trailer guidance line is active.

• Adaptive Cruise Control: Adaptive CruiseControl (ACC), it allows the driver to select thecruise control set speed and following gap. Thefollowing gap is the following time between yourvehicle and a vehicle detected directly ahead inyour path, moving in the same direction. If novehicle is detected in your path, ACC works likeregular cruise control. Turning OFF the TCS orStabiliTrak® system will disengage the cruisecontrol.

• Forward Automatic Braking: If the vehicle hasFCA, it also has Forward Automatic Braking(FAB), which includes Intelligent Brake Assist(IBA). When the system detects a vehicle ahead inyour path that is traveling in the same directionthat you may be about to crash into, it can providea boost to braking or automatically brake thevehicle. This can help avoid or lessen the severityof crashes when driving in a forward gear.Depending on the situation, the vehicle mayautomatically brake moderately or hard. Thisforward automatic braking can only occur if avehicle is detected. This is shown by the FCAvehicle ahead indicator being illuminated.

• Forward Collision Alert: The Forward CollisionAlert (FCA) system may help to avoid or reducethe harm caused by front-end crashes. Whenapproaching a vehicle ahead too quickly, FCAprovides a red flashing alert on the windshield andrapidly beeps or pulses the driver seat. FCA alsolights an amber visual alert if following anothervehicle much too closely. FCA detects vehicleswithin a distance of approximately 197 ft (60 m)and operates at speeds above 25 mph (40 km/h).If the vehicle has Adaptive Cruise Control (ACC),it can detect vehicles to distances ofapproximately 360 ft (110 m) and operates at allspeeds.


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• Front Pedestrian Braking: The Front PedestrianBraking (FPB) system may help avoid or reducethe harm caused by front end crashes with nearbypedestrians when driving in a forward gear. FPBdisplays an amber pedestrian indicator when anearby pedestrian is detected directly ahead.When approaching a detected pedestrian tooquickly, FPB provides a red flashing alert on thewindshield and rapidly beeps or pulses the driverSafety Alert Seat. FPB can provide a boost tobraking or automatically brake the vehicle. TheFPB system can detect and alert to pedestrians ina forward gear at speeds between 5 mph (8 km/h)and 50 mph (80 km/h). During daytime driving, thesystem detects pedestrians up to a distance ofapproximately 131 ft (40 m). If FPB detects it isabout to crash into a pedestrian directly ahead,and the brakes have not been applied, FPB mayautomatically brake moderately or hard. Duringnighttime driving, system performance is verylimited.

• Front Vision Camera: The Front Vision Cameraprovides a view of the area in front of the vehicle.The view displays after shifting from R to a forwardgear, or by touching CAMERA in the infotainmentdisplay, and when the vehicle is moving forwardslower than 5 mph (8 km/h). The Front VisionCamera also displays when the Parking Assistsystem detects an object within 12 in (30 cm).

• Lane Change Alert: The Lane Change Alert(LCA) system provides outside side mirror alertsto help the driver avoid crashing into a movingvehicle detected in their side blind spot (or zone)or a vehicle that is rapidly approaching their blindspot during a lane change maneuver.

• Lane Departure Warning: Lane DepartureWarning (LDW) may help avoid crashes due tounintentional lane departures. It may provide awarning if the vehicle is crossing a detected lanemarking without using a turn signal in the lanedeparture direction. This system is part of theLane Keep Assist (LKA) system.

• Lane Keep Assist: Lane Keep Assist (LKA) mayassist the driver by gently turning the steeringwheel if the vehicle approaches a detected lanemarking without using a turn signal in thatdirection. It may also provide a Lane DepartureWarning (LDW) system alert as the lane markingis crossed. The LKA system will not assist orprovide an LDW alert if it detects that the driver isactively steering.

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• Parking Assist: With RPA, and if equipped withFPA, as the vehicle moves at speeds of less than5 mph (8 km/h) the sensors on the bumpers maydetect objects up to 8 ft (2.5 m) behind the vehicleand 4 ft (1.2 m) in front of the vehicle within a zone10 in (25 cm) high off the ground and belowbumper level. The Parking Assist system does notdetect children, pedestrians, bicyclists, animals, orobjects located below the bumper or that are tooclose or too far from the vehicle. The instrumentcluster may have a parking assist display withbars that show “distance to object” and objectlocation information for the Parking Assist system.As the object gets closer, more bars light up andthe bars change color from yellow to amber to red.

• Rear Cross Traffic Alert: Rear Cross TrafficAlert (RCTA) displays a red warning triangle with aleft or right pointing arrow on the RVC screen towarn of traffic coming from the left or right. Thissystem detects objects coming from up to 65 ft(20 m) from the left or right side of the vehicle.When an object is detected, either three beepssound from the left or right or three Safety AlertSeat pulses occur on the left or right side,depending on the direction of the detected vehicle.Use caution while backing up when towing atrailer, as the RCTA detection zones that extendout from the back of the vehicle do not movefurther back when a trailer is towed.

• Rear Parking Assist : Rear Parking Assist (RPA)uses sensors on the rear bumper to assist withparking and avoiding objects while in R(Reverse). It operates at speeds less than 5 mph


(8 km/h). RPA may display a warning triangle onthe Rear Vision Camera screen and a graphic onthe instrument cluster to provide the objectdistance. In addition, multiple beeps or seatpulses may occur if very close to an object.

• Rear Vision Camera: When the vehicle is shiftedinto R (Reverse), the Rear Vision Camera (RVC)displays an image of the area behind the vehiclein the infotainment display. The previous screendisplays when the vehicle is shifted out of R after ashort delay. To return to the previous screensooner, press a button on the infotainment display,shift into P (Park), or reach a vehicle speed of5 mph (8 km/h). Select Front or Rear Camera onthe camera screen to view the front or rear cameraviews. Select Guidance Lines on the camerascreen to enable or disable the guidance lines.

• Safety Alert Seat: The Safety Alert Seat providesthe driver the option of getting haptic seat-bottomvibration crash avoidance alerts or beeping. Tochange from one to the other, see “Comfort andConvenience” under Vehicle Personalization inthe Owner Manual.

• Side Blind Zone Alert: The Side Blind Zone Alert(SBZA) system is a lane changing aid that assistsdrivers with avoiding crashes that occur withmoving vehicles in the SBZA (or spot) areas.When the vehicle is in a forward gear, the left orright side mirror display will light up if a movingvehicle is detected in that blind zone. If the turnsignal is activated and a vehicle is also detectedon the same side, the display will flash as an extrawarning not to change lanes. This system is partof the LCA system.

Safety— Surround Vision

Surround Vision

Notice: The Surround Vision cameras have blindspots and will not display all objects near thecorners of the vehicle. Folding side mirrors that areout of position will not display the surround viewcorrectly.Surround Vision displays an image of the areasurrounding the vehicle, along with the front or rearcamera views in the center stack. The front camera is inthe grille or near the front emblem, the side camerasare on the bottom of the outside rearview mirrors, andthe rear camera is above the license plate.

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1 = Areas displayed by the Surround Vision cameras.2 = Areas not displayed by the Surround Visioncameras.

Steering

The Acadia is equipped with a belt driven electric powersteering system which reduces the amount of effortneeded to steer the vehicle by utilizing the powersteering control module to control the power steeringmotor to maneuver the steering rack. The powersteering control module uses input from the torquesensor, motor rotational sensor, battery voltage circuitand GMLAN serial data circuit to determine the level ofmotor assist. Vehicle speed and engine speed from theGMLAN serial data circuit is also used to adjust theamount of steering assist needed to steer the vehicle.At low speeds more assist is provided for easy turningduring parking maneuvers. At higher speeds less assistis provided for improved road feel and directionalstability


The belt driven electronic power steering systemconsists of the following components:• A belt drive and a ball nut mechanism.• A power pack which contains the power steering

control module, its sensors, and the powersteering motor.

• A torque sensor.• The steering gear (rack and pinion).

Suspension

Front Suspension

The Acadia is equipped with a MacPherson strut frontsuspension. The front suspension absorbs the impactof the tires travelling over irregular road surfaces anddissipates this energy throughout the suspensionsystem. This process isolates the vehicle occupantsfrom the road surface. The rate at which thesuspension dissipates the energy and the amount ofenergy that is absorbed is how the suspension definesthe vehicle’s ride characteristics. Ride characteristicsare designed into the suspension system and are notadjustable. The suspension system must allow for thevertical movement of the tire and wheel assembly asthe vehicle travels over irregular road surfaces whilemaintaining the tire's horizontal relationship to the road.

Rear Suspension

The Acadia is equipped with an independent 5-link rearsuspension. The rear suspension maintains therelationship of the rear axle to the body and controls thetorque reaction on acceleration and braking. Rearsuspension adjustment is achieved through adjustabletoe links and lower control arms. The rear coil springsare retained between the body and the lower controlarm. Rubber insulators isolate the coil spring at bothtop and bottom. The rear suspension consists of2 shock absorbers attached to the lower control armand the reinforced body areas.

Electronic Suspension Control System (AvailableSLT-2 and Denali)

The electronic suspension control system individuallycontrols the damping force of each of the 4 shockabsorbers in order to keep the vehicle body as calm aspossible. Changes of the damping forces can beaccomplished within milliseconds. Suspensioncharacteristics can be changed at any time byactivating the Sport mode or Tour mode. TheContinuous Damping Control (CDC) system providessuperior vehicle ride and handling under a variety ofpassenger and loading conditions. The system is fullyautomatic and uses a computer controller tocontinuously monitor vehicle speed, wheel to bodyposition, lift/dive, and steering position of the vehicle.The controller then sends signals to each shockabsorber to independently adjust the damping level toprovide the optimum vehicle ride.

Transmissions

HydraMatic™ 6T50 Automatic 6-Speed FWD withStart/Stop — RPO M2D

4492387

The HydraMatic™ 6T50 is a 6-speed, front wheel drive,electronically controlled, automatic overdrive transaxlewith an electronically controlled torque converter clutchand a surge accumulator for the start/stop system. Thistransmission features Gen 3 upgrades implemented toenhance efficiency. The pump, for example, has beenmoved off-axis, which allows better sealing of thetorque converter, reducing pump flow demands toenhance fuel economy. Additionally, the pump is now abinary vane-type, which allows lower powerconsumption during times of lower flow demands and athigher engine speeds. This transmission is used withthe 2.5L engine.

HydraMatic™ 6T70 Automatic 6-Speed AWD —RPO M7U

4492450


The HydraMatic™ 6T70 transmission is part of GM'sfamily of technically advanced, fuel saving 6-speedautomatics designed to optimize efficiency whiledelivering exceptional smoothness and an excellentfeeling of performance. Because of the wide ratiospread, first gear is a very high ratio, which providesbrisk acceleration from a stop. Sixth gear is anoverdrive ratio, which keeps the engine revolutions aslow as possible for highway cruising, reducing enginefriction losses and improving fuel economy. Instead of"folding" the transmission around the end of atransversely mounted engine (which has been one ofthe dominant GM transaxle design conventions), the6T70 contains all of the gearing in line with thecrankshaft centerline of the engine. The advantages ofthis layout can translate to a shorter overall vehiclelength, more interior room and lower powertrain height.This transmission is used with the 3.6L engine.

HydraMatic™ 6T70 Automatic 6-Speed FWD —RPO M7W

The HydraMatic™ 6T70 transmission is part of GM'sfamily of technically advanced, fuel saving 6-speedautomatics designed to optimize efficiency whiledelivering exceptional smoothness and an excellentfeeling of performance. Because of the wide ratiospread, first gear is a very high ratio, which providesbrisk acceleration from a stop. Sixth gear is anoverdrive ratio, which keeps the engine revolutions aslow as possible for highway cruising, reducing enginefriction losses and improving fuel economy. Instead of"folding" the transmission around the end of atransversely mounted engine (which has been one ofthe dominant GM transaxle design conventions), the6T70 contains all of the gearing in line with thecrankshaft centerline of the engine. The advantages ofthis layout can translate to a shorter overall vehiclelength, more interior room and lower powertrain height.This transmission is used with the 3.6L engine.

AWD with Active Twin Clutch — Acadia All-Terrain

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The AWD system with Active Twin Clutch deliversgreater handling, stability and driver confidence bypreemptively and electronically splitting torque betweenthe rear wheels to provide additional control versus a50/50 split in a single clutch system.It provides the following benefits:• Specific All-Terrain mode in place of the Off-Road

mode on the drive mode selector.• Enhanced traction, stability and performance

during vehicle acceleration and cornering duringdry normal conditions.

• Optimal handling and improved traction in wet/snowy/icy conditions.

• Improved vehicle response when road traction isnot uniform, such as when the right side of thevehicle is on ice and the left side is on drypavement.

• Active Twin Clutch with active torque bias hasincreased capability to add stability across alldriving conditions.

• A fuel economy benefit is realized by not pushingtorque when it is not needed.

Power Transfer Unit

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The GKN model 761 power transfer unit (PTU) ispositioned in the right side of the vehicle and in modeldependent applications is bolted to the transmission viaan adapter plate. The primary function of the PTU is toreceive power from the transmission and transfer itthrough the propeller shaft to the rear differential usinghelical and hypoid gear sets. The PTU housing, cover,extension housing, and rear output shaft housing are acast aluminum design. Gear tooth clearances andbearing preloads are maintained by shims locatedbehind the bearing races. The housings, internal gears,and bearings are not serviceable components. Ifhousing, gear set, or bearing damage occurs, theassembly must be replaced. The PTU fluid is fill-for-lifewith no maintenance fluid change intervals required.


The disconnect-design PTU has the ability to internallyengage and send power and torque to the rearpropeller shaft, activating AWD mode. Shifting isperformed by a PTU mounted actuator motor, internallinear and rotary cams, and shift collar. The actuatormotor operates as directed by the rear differentialclutch control module to perform the shifting operations.During normal driving situations, the PTU operates inFWD mode with no rotation of the rear propeller shaft.The rear differential clutch control module monitorswheel slip based on the inputs from the wheel speedsensors and vehicle speed sensor. When the vehicleexperiences a wheel slip condition, the control modulesends a pulse width modulated (PWM) signal to thePTU actuator motor. The actuator motor rotates theworm gear and rotary cam, moving the shift collar toengage AWD and propeller shaft rotation. AWD modewill remain active until the slip condition has stopped.The process would repeat if wheel slip is detectedagain.

Drive Mode Control

The Drive Mode Control has the following Modes:Front-Wheel Drive (FWD), Sport, All-Wheel Drive(AWD), Snow/Ice, Tow/Haul, and Off-Road or AllTerrain. Rotate the Drive Mode Control knob on thecenter console to select a mode. Continue turning theknob through the available modes as needed.The various modes function as follows:• FWD : Vehicle is in FWD Mode. Use this mode

during normal driving conditions.• Sport : Sport Mode improves vehicle handling

and acceleration on dry pavement. When active,Sport Mode modifies steering efforts, transmissionshifting, AWD torque, and suspension tuning(when equipped with Continuous DampingControl). For AWD vehicles, choosing Sport Modealso engages AWD Mode.

• AWD (AWD Vehicles Only) : AWD Modeprovides drive torque to all four wheels. SelectAWD to improve traction and control on slipperyroad surfaces, such as gravel, sand, wetpavement, snow, and ice. When in AWD Mode,the AWD Mode indicator will illuminate.

• Snow/Ice (FWD Vehicles Only) : Snow/Ice Modeimproves vehicle acceleration on snow and icecovered roads.

• Tow Haul : Available when the vehicle is in FWDor AWD Mode. Use this mode to assist inmaintaining desired vehicle speeds when drivingon downhill grades by using the engine andtransmission to slow the vehicle.

• Off-Road (AWD Only) or All-Terrain: Vehicle isin AWD Mode. Use this mode for off-roadrecreational driving. Off-Road optimizes traction inoff-road conditions (gravel, sand, mud). All Terrainfunctions like Off-Road mode, but adds enhancedhill climbing capability & unique tuning.

Drive Mode Control Knob FWD

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1. Normal 2x4 FWD2. Snow3. Sport4. Trailer/Tow (If equipped - not shown) (Shown on

Drive Mode Control Knob AWD)

Drive Mode Control Knob AWD

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1. Normal 2x4 FWD (AWD Disconnect)2. 4x4 AWD3. Sport4. Off-Road or All-Terrain (Depending on model)5. Trailer/Tow (If equipped)


Towing the Vehicle— RecreationalVehicle Towing

Towing the Vehicle

Have the vehicle towed on a flatbed car carrier. Neveruse a sling type lift or damage will occur. Use ramps tohelp reduce approach angles if necessary. A towedvehicle should have its drive wheels off the ground.

Dinghy Towing — 2.5L

This vehicle was not designed or intended to be dinghytowed.

Dinghy Towing — AWD 3.6L

If the vehicle is all-wheel drive, it can be dinghy towedfrom the front. These vehicles can also be towed byplacing them on a platform trailer with all four wheelsoff of the ground. These vehicles cannot be towedusing a dolly.

Dinghy Towing — FWD 3.6L

If the vehicle is front-wheel drive, it can be dinghytowed from the front. These vehicles may also betowed by putting the front wheels on a dolly.

Trailer TowingThe Acadia base towing capacity is 2,000 lbs (907 kg).Vehicles equipped with the Trailer Towing Packagehave a towing capacity of 5,200 lbs (2,359 kg). Use theTow/Haul mode when pulling a heavy trailer to reducethe frequency of transmission shifts and improve thecontrol of vehicle speed.

Special Tools

The following new tools were released for the 2017Acadia:

Special Tools— Tool Number and DescriptionTool Number Description

DT-47791-B Converter Seal Driver

DT-49131 Seal Staking Tool

EN-42385-70 Head Bolt Thread Repair Torque Plate

EN-44226-5 Crankshaft Protector Button

EN-46335-A Valve Spring Compressor (On-vehicle)

EN-49941 Piston Pin Retainer Remover

EN-51333 Timing Chain Retainer Set

EN-51766 Rear Seal Installation Pilot

DT-51329-A Driveshaft Remover

DT-51834 Seal Installer, RH Input & Pinion Cassette

DT-51835 Seal Installer, LH Input & IDS Cassette

Training Courses

The majority of the systems found on this vehicle aretaught in GM’s core curriculum from a conceptualtheory and operation perspective. The North Americantechnical training core curriculum structure is systembased.To access all of the available training courses in theUnited States, visit the following website:www.centerlearning.comIn Canada, Go to GM GlobalConnect and selectCentre of Learning

Training Course Name or System— Course Number and DescriptionCourse Name or System Course Number and Description

New Model Feature2017 GMC Acadia New Model Features

#10317.40W — 2017 GMC Acadia New Model Features (U.S.and Can)

EngineGasoline, 4 Cylinder L4, 2.5L, DI, DOHC, VVT, DCVCP —

RPO LCVGasoline, 6 Cylinder, V6, 3.6L, DI, DOHC, VVT — RPO LGX

#16440.17D-V — Engines: New and Updates for RPOs LCV,LTG, LL0 (United States Only)

#16043.16H — Gen 2 Overhaul/Repair Certification(Canada Only)


Training Course Name or System— Course Number and Description (cont'd)Course Name or System Course Number and Description

#16440.20D — Engines: New and Updates for RPOs LF4,LGX, LGW, L3A, LV7, LE2 and LWN (United States Only)

TransmissionHydraMatic™ 6T50, 6T70 6-Speed Automatic Transmissions

— RPO M2D, M7U and M7W

#17440.12D — Transmissions New & Updates: HydraMatic6T40/45 (U.S. only)

#17440.13D-R2 — Transmissions New & Updates: 6T70/6T75, 6L50/6L80/6L90, 4L60/4L70 (U.S. only)

#17036.16H – 6T70 Transmission Overhaul & Service(Can only)

#17036.01V – 6T40/45 Unit Repair (Can only)

Safety Systems Forward Collision Alert / Lane DepartureWarning and Rear Vision Camera

#22048.42W1-W3 GM Safety Systems 1-3 (United States andCanada)

Version Information

Version 1

Modified —

Trademark Footnotes

ACDelco® is a Registered Trademark of GeneralMotors LLCAndroid™ Auto is a Trademark of Google Inc.Apple® is a Registered Trademark of Apple Inc.The Bluetooth® Word Mark and Logos areRegistered Trademarks Owned by BluetoothSIG, Inc.CarPlay™ is a Trademark of Apple Inc.dexos® is a Registered Trademark of GeneralMotors LLC

dexos1® Icons are Registered Logos of GeneralMotors LLCGoogle® is a Registered Trademark of Google Inc.HydraMatic™ is a Trademark of GeneralMotors LLCIntelliLink® is a Registered Trademark of GeneralMotors LLC (United States)iPhone® is a Registered Trademark of Apple Inc.OnStar® is a Registered Trademark of OnStar LLCStabiliTrak® is a Registered Trademark of GeneralMotors LLC

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform thesetechnicians of conditions that may occur on some vehicles, or to provide information that could assist in the properservice of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do ajob properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that yourvehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from theinformation.

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