Introduction

Congratulations, you have just purchased the only true independent air ride suspensions. This technology has been developed and patented by Suspension Technology Industries. This manual is designed to assist you in the operation, maintenance, and, if applicable, installation of your Suspension Technology Industries air suspensions. Your air suspension assemblies consist of the main beam, air bag assemblies, swing arm/torque rod assemblies, and wheel end kit (if purchased). Additionally, if you have purchased one of our pre-assembled air control kits, the proper set-up and maintenance guidelines are contained in this manual as well. Note that the air control kit , specifically the height control valves, is not set-up for operation prior to leaving the STI factory, and must be done by the trailer manufacturer, trailer dealer, or end user, depending on your circumstances. See the section in this regarding adjusting the height control valves for additional information. Additionally, visit our website for installation information. Adequate installation and service is paramount for the life of the suspension, trailer and related components, as well as the safety of all. The purpose of this manual is to provide a guideline for the installation, maintenance, and use of the supplied components. There are a number of variations in each individual’s installation and servicing practices, and this manual by no means attempts to cover them all. This manual is simply meant as a guide in assisting you, and above all, putting safety first. Warranty information is located in the back of this manual. Please be aware and take extra precaution anywhere throughout this manual where the following safety warning sign is displayed:

WARNING! DO NOT get under trailer without sufficient supports, jack stands, etc., Air suspension may rapidly, suddenly, and without notice lower several inches causing crushing injury and/or death.

Great ride, full air isolation…

WWW.RIDETHEAIR.COM

Table of Contents

Page Description 4 General information 6 Installation 13 Torque specifications 14 Wheels and rims 16 Toe and camber information 19 Air kit installation instructions 22 Height control valve adjustment 24 Operation of air ride system

28 Suspension failure during travel

30 Maintenance

34 Bearings, seals, and brake parts 37 Hydraulic disc brakes used in Air-Over-Hydraulic systems 41 Torque rod replacement

44 Storage 45 Serial and Model number location 48 Air suspension components identification and definitions 54 Trouble shooting 58 Suspension record information 59 LBS warranty

60 Warranty Labor Allowance 61 Brake / Wheel End Warranty 62 Warranty procedure information

63 Return authorization form 64 Ordering Parts 64 Credit Policy

General Information The following page has a depiction of a typical air suspension assembly, complete with parts list to assist you in identifying individual parts or assemblies, as well as to help you if the need for replacement parts arises. The “backbone” of the air suspension is the axle assembly. This assembly will be attached to the framework of your trailer, typically using the optional frame brackets to weld to your existing trailer frame. The air suspension also contains two air spring assemblies, located on the rear of the axle assembly. Two individual air bags come pre-plumbed with air lines and fittings for connection to your air system. A “driver side” and a “curb side” torque rod assembly, complete with spindle type of your choice is pre-set to a specific angle to give you air suspension the desired ride height. Refer to the following for the various Design Height (torque rod angle) options:

design height insert.dwg

5.00 DESIGN HEIGHT3.75 DESIGN HEIGHT

2.50 DESIGN HEIGHT1.25

DESIGNHEIGHT

10.32

5.23

15.55

2.50DESIGNHEIGHT

10.32

6.48

16.80

3.75DESIGNHEIGHT

10.32

7.73

18.05

5.00DESIGNHEIGHT

10.32

19.30

8.98

1.25 DESIGN HEIGHT

(Note: The above illustration does not apply to Cargo-Max style suspensions)

If purchased, optional wheel end equipment can be supplied with the air suspension as well. Air suspensions are supplied standard with electric drum brake wheel end kits. Options are available for different type wheel end kits, see price schedule.

STA

MP

ED

MO

DE

L &

SE

RIA

L #

LOC

ATIO

N

19

BO

LT T

OR

QU

E CH

ART

3/4

- 16

5/8

- 11

3/8

- 16

SIZ

EFT

- L

BS

420

220

45 * 16

171

716

213

1714

155

2

109

112

TOR

QU

E R

OD

AS

S'Y

. - C

UR

B SI

DE

3/4-

16 H

IGH

NU

T

1/4T

PLU

G

1/4T

UN

ION

TEE

3/8-

16x0

.75

HH

CS

TOR

QU

E R

OD

AS

S'Y

. - D

RIV

ER S

IDE

3/8

SP

LIT

LOC

K W

ASH

ER

3/4

HD

FLA

T W

ASH

ER

3/4x

3-1/

16x6

U-B

OLT

3/4x

3-1/

16x7

U-B

OLT

412 2 22

211612

17 19 2018

1 12813 1514

THR

US

T W

ASH

ER

BE

AM

WE

LDM

ENT

AX

LE A

SS

EMBL

YW

HE

EL

EN

D K

IT -

CU

RB

SID

EW

HE

EL

EN

D K

IT -

DR

IVER

SID

E

AIR

SP

RIN

G A

SSEM

BLY

FRA

ME

BR

AC

KE

T K

IT -

CU

RB

SID

EFR

AM

E B

RA

CK

ET

KIT

- D

RIV

ER S

IDE

CH

AIN

CR

AN

K -

CU

RB

SID

EC

HA

IN C

RA

NK

- D

RIV

ER S

IDE

BIL

L O

F M

ATE

RIA

L

14

18

1 119 1110

1 15 6 7

ITEM

QTY 2 24

2 31D

ES

CR

IPTI

ON

51315

DR

UM

BR

AKE

DIS

C B

RAK

E

WH

EE

L E

ND

KIT

NO

TES:

1. W

HE

EL

EN

D K

ITS

& T

OR

QU

E R

OD

AS

SE

MB

LIE

S A

RE

SH

OW

N F

OR

ILLU

STR

ATI

ON

PU

RP

OS

ES

ON

LY.

ACTU

AL P

ARTS

MAY

VAR

Y IN

APP

EAR

ANC

E. S

EE S

PEC

IFIC

M

OD

EL

NU

MB

ER

DR

AW

ING

FO

R A

CTU

AL P

ARTS

.

2. H

EIG

HT

CO

NTR

OL

VA

LVE

S A

RE

SH

OW

N F

OR

INS

TALL

ATI

ON

PU

RP

OS

ES

ON

LY.

THE

Y A

RE

NO

T P

AR

T O

F TH

IS B

ILL

OF

MAT

ERIA

LS.

SEE

HEI

GH

T C

ON

TRO

L VA

LVE

KIT

FOR

BIL

L O

F M

ATER

IALS

.

3. I

NS

TALL

WH

EE

L E

QU

IPM

EN

T (I

F A

PP

LIC

AB

LE)

PE

R M

AN

UFA

CTU

RE

R'S

OP

ER

ATI

ON

, MA

INTE

NAN

CE,

AN

D S

ERVI

CE

MAN

UAL

. CH

ECK

YOU

R W

HEE

L EN

D C

OM

PON

ENTS

TO S

EE

WH

ICH

MA

NU

FAC

TUR

ER

'S M

ANU

AL A

PPLI

ES.

4. F

ILL

EA

CH

TO

RQ

UE

RO

D H

OU

SIN

G W

ITH

GR

EA

SE

OR

OIL

PE

R Y

OU

R S

US

PE

NSI

ON

SPE

CIF

ICAT

ION

S U

PON

CO

MPL

ETIO

N O

F H

UB

ASSE

MBL

Y.

3/8-

16x1

.00

HH

CS

4

9

4

LBS

Typ

ical

Gen

eral

Ass

embl

y.dw

g

NO

TE: H

EIG

HT

CO

NTR

OL

VA

LVE

ASSE

MBL

Y (Q

TY. 2

)N

OT

INC

LUD

ED

UN

LES

S O

RD

ERED

SEP

ARAT

ELY

HE

IGH

T C

ON

TRO

L V

ALV

E AS

SEM

BLY

HE

IGH

T C

ON

TRO

L V

ALV

E AS

SEM

BLY

* T

HE

3/8

"-16

HE

X H

EA

D C

AP S

CR

EWS

(#14

) USE

D

FO

R A

TTA

CH

ING

TH

E BE

AM W

ELD

MEN

T TO

TH

EA

IR S

PR

ING

AS

SE

MB

LY H

AVE

A M

AX. B

OLT

T

OR

QU

E O

F 2

5 FT

. LBS

.

TYPI

CA

L G

ENER

AL

ASS

EMB

LY(S

EE

THE

GE

NE

RA

L AS

SEM

BLY

DR

AW

ING

AN

D T

HE

SPE

CIF

IC M

OD

EL

DR

AWIN

G P

RO

VID

ED W

ITH

YO

UR

SU

SPE

NS

ION

FO

R E

XAC

T SU

SPEN

SIO

N C

OM

PON

EN

TS)

818

205

1 12

Installation

Suspension Installation Suggestions It is important to properly install the suspension assembly to the trailer to ensure safe operation, as well as optimum durability of all related parts. It is the responsibility of the suspension installer to align the axles correctly. Although most trailer manufacturers have a time-proven technique for the installation of axles, this manual can be used as a general guideline. The installer is responsible to correctly install the suspensions, taking into account all standard weld procedures, any hardware installation, and proper tolerances. If installing on trailer with an existing suspension system, remove assembly and all related hardware and/or weld evidence. Trailer frame components must be flat and square to assure proper installation of new air suspension assembly. Read through entire installation instruction prior to actual assembly. Each type of trailer is unique. Use these instructions as a guideline. Actual installation will vary with each individual trailer. Additional installation information is available at our website WWW.RIDETHEAIR.COM under the LBS products section. It is imperative to follow all safety guidelines shown in this manual, as well as use of safety glasses at all times during the assembling or disassembling of axles and their components.

WARNING ! DO NOT get under trailer without sufficient supports, jack stands, etc., Air suspension may rapidly, suddenly, and without notice lower several inches causing crushing injury and/or death.

Required Tools and Equipment The following is a list of tools and equipment most commonly used and needed for installing our air suspensions. Each individual installer may have additional tools that they will find helpful. MIG Welder Pneumatic grinder Cutting torch (2) 25’ minimum tape measures (3) Plumb bobs Paint marker or soap stone Floor jack Tubing cutter Torque wrench Tubing flare kit Various hand tools Suspension Capacity and Specific Model Number It is assumed that the suspension(s) about to be installed is of the correct capacity and dimensions per the STI LBS Series Suspension Calculator sheet, filled out and submitted prior to ordering your suspension(s). Your STI salesperson can help you to identify the correct air suspension for your specific application. The axle capacity is typically determined by subtracting the hitch load weight from the gross vehicle weight. The remainder will be the load capacity needed to be support by the suspension(s).

Determining Location of Suspension(s) A few things to keep in mind when determining the location to install the air suspension(s) on your trailer are as follows:

- The hitch weight for a conventional bumper should be 10% to 14% of the gross vehicle weight of the trailer. The remaining 86% to 90% of the weight will be carried by the air suspension(s). The suspension(s), wheels and tires will have to be of sufficient capacity rating to support this load.

- The hitch weight for fifth wheel and gooseneck type hitches should be 15% to 20% of the gross

vehicle weight of the trailer. The remaining 80% to 85% of the weight will be carried by the air suspension(s). The suspension(s), wheels and tires will have to be of sufficient capacity rating to support this load.

- To ensure proper tracking, the suspension(s) must be positioned perpendicular to the centerline of

the trailer frame. The accuracy of this placement should be with +/- 1/2°. For trailer installations with multiple suspensions, each suspension being installed must be parallel with each other within 1/16” when measured at the wheel centers.

- In the case where tandem or tri-axles are being used, the suspensions should be installed so that

there is a minimum of 1” clearance between the tires when the suspensions are fully loaded. To determine this spacing, find the tire manufacturer’s maximum diameter for your specific tire and add a minimum of 1” to that dimension for your spacing value. This will be the center-to-center dimension of your suspensions.

Positioning of Suspensions on Trailer Frame The attachment location of the air suspension(s) to the trailer frame is determined by measuring the distance from the center of the hitch to the center of gravity of the trailer. (The center of gravity is the point in the trailer that if entirely supported at that point, would balance the trailer in perfect equilibrium). We will call this distance “CG Distance” in the illustration below. This distance is to be divided by the percentage of the gross vehicle weight to be carried by the suspension(s). The result will be the distance from the hitch to the center of the suspension. This is shown as “Suspension Distance” In the case of tandem axles, it would be the distance from the hitch to the parallel centerline between the two spindles. On a tri-axle, it would be the distance from the hitch to the center spindle location.

Once the suspension distance(s) has been determined, mark a line on the trailer frame, using paint or soapstone, for the centerline of each suspension. You will need to measure from the hitch point to both the left side and right side of the frame to verify that your suspension centerline is square to the centerline of the trailer, as shown in the illustration below.

After the location of the suspension(s) has been determined, you must decide the best method in welding the suspensions to the trailer frame. An optional accessory to the suspension is a frame bracket kit. A frame bracket assembly can be welded to each side of the trailer frame, and then the suspension bolted directly to the frame brackets by use of 5/8” bolts. Use of the frame brackets allows future removal of the suspension if desired. Note: Replace the frame bracket hardware if frame brackets are loosened or removed. They have been properly torqued at factory. The suspensions can be welded directly to the trailer frame in lieu of using frame brackets:

TOP VIEW

FRONT VIEW SIDE VIEW

SUSPENSION IS WELDED DIRECTLYTO TRAILER'S BOX TUBE FRAMEWORK

PERPENDICULAR TO CENTERLINE OF TRAILERCENTERLINE OF SUSPENSION MUST BE

The frame brackets can be welded to the trailer frame, and then it is possible for the suspension to be unbolted from the trailer:

TOP VIEW

FRONT VIEW SIDE VIEW

SUSPENSION IS WELDED TOREMOVABLE FRAME BRACKET

CENTERLINE OF SUSPENSION MUST BEPERPENDICULAR TO CENTERLINE OF TRAILER

Standard frame bracket dimensions are shown in the following illustration:

23.13 REF.

3.80

9.92 5.74

3.06

REPLACE FRAME BRACKET HARDWAREIF LOOSENED OR REMOVED

When suspensions are being welded to trailer frames comprised of angle, I-beam / H-beam, or channel, it is recommended that additional structural support be added at the points of suspension attachment. Some typical examples of this are shown below:

ADDITIONAL REINFORCEMENTTO FRAME IS RECOMMENDED

TO FRAME IS RECOMMENDEDADDITIONAL REINFORCEMENT

TO FRAME IS RECOMMENDEDADDITIONAL REINFORCEMENT

Welds All welds should conform to AWS (American Welding Society) standard specifications. Welds should typically be ¼” fillet weld minimum. The suspensions should always be a room temperature prior to welding to the trailer frame. Do no bring suspensions in from non-heated storage and weld while still cold. Ideal temperature for welding the suspensions is about 70° F. Additionally, do not “test the arc” of the weld on the suspension’s axle beam. Suspension Technology Industries supplies air ride suspensions to trailer manufacturers and end users for the intent of being installed on an existing trailer. Therefore we have little or no control over the assembly of these units to the trailer. We cannot be responsible for warranty of improperly installed suspensions. Fit The outermost frame width of the trailer should not exceed the “Max. Frame Width” dimension of the specific Suspension Technology drawing for that particular suspension. Additionally, that dimension will always be less than the “Inside of Arms” dimension on the same drawing, assuring that no part of the trailer frame will interfere with the movement of the suspension’s swing arms. It is imperative that the centerline of the suspension(s) is 90°, or perpendicular, to the centerline of the trailer. Failure to do so will cause the trailer to “dog-track” behind the tow vehicle. That is, the suspensions will align themselves with the line of travel of the tow vehicle, but the trailer itself will travel at an angle.

Wheel End Equipment (brakes and hubs) Your suspension is typically supplied with wheel end equipment. It can remain on the suspension during installation. If they are removed for maintenance, inspection etc., re-attach wheel end kits to the mounting plate on the torque rod assembly with the provided hardware. Torque all bolts and/or nuts to the respective minimum torque for that particular size fastener per the value shown in the torque specifications chart on the following page

WHEEL END MOUNTING PLATE

WHEEL END MOUNTING PLATE(SHOWN WITH WHEEL END KIT INSTALLED)

Torque Specifications The following specifications are to be used with all SAE Grade 8, unlubricated fasteners, other than lug nuts:

Bolt Size (inches) Torque (FT-LBS) 1/4-20 12 1/4-28 14

5/16-18 25 5/16-24 25 3/8-16 * 45 3/8-24 50

7/16-14 70 7/16-20 80 1/2-13 110 1/2-20 120

9/16-12 150 9/16-18 170 5/8-11 220 5/8-18 240 3/4-10 380 3/4-16 420 7/8-9 600 7/8-14 660

1-8 900 1-12 1000

1-1/8-7 1280 1-1/8-12 1440 1-1/4-7 1820

1-1/4-12 2000

* The 3/8”-16 hex head cap screws for attaching the beam weldment to the air spring assembly has a modified torque rating of 25 FT-LBS. See the Typical General Assembly illustration on page five of this manual for clarification of this hardware. Note: If any hardware on the suspension is removed or loosened, be sure that it is again torqued to the proper specifications per the above chart.

Wheels and Rims Standard LBS Suspension Unless you purchased our Cargo-Max line of air suspensions, wheels and/or rims are not included with the suspension package. (Cargo-Max uses a proprietary rim, only available from STI). Additionally, STI does not supply tires. A rim and tire size would have been specified on the Customer Inquiry sheet submitted with the purchase order when the air suspensions were ordered. These wheels/rims can now be installed onto the wheel end kits.

Trailers have higher wheel loading than passenger cars or trucks. Tandem and tri-axles do not steer, and wheels are subjected to high twisting side loads in tight, slow turns. This causes the wheel to flex which tends to loosen wheel lug nuts over time. Always check lug nut torque before each trip. A suitable torque wrench is a worthwhile investment considering the value of your trailer.

Wheel lug nut torque is usually much higher than that specified for passenger car wheels. Check your particular trailer's recommended specifications. Torque all lug nuts per the following specification table. Recheck lug torque after 50 and 100 miles, and periodically thereafter. Do not drive a loaded trailer with a missing lug nut or damaged lug bolt. Torque all lug nuts in the sequence shown in the following diagram, specific to your number of lugs.

Typical or Standard Wheel Torques

Lug Nut Torque Sequence

Lug Nut Torque in FT-LBS 1/2”-20 60° cone nut 90 to 120 9/16”-18 60° cone nut 90 to 120

5/8”-18 90° nut 175 to 225 5/8”-18 flange nut 275 to 325

¾”-16 ball seat 450 to 500

Cargo-Max Wheels STI manufactures the Cargo-Max line of air ride suspensions, which features a proprietary aluminum wheel which is included with the suspension assembly. The torque specification for its 5/8” studs and aluminum rim is as follows:

Cargo-Max Lug Nut Torque

Cargo-Max Lug Nut Torque Sequence

General Wheel Information Suspension Technology Industries’ suspensions include hubs and drums that are compatible with many wheels used in the trailer industry that have matching bolt patterns. Suspension Technology does not manufacture wheels (other than Cargo-Max), nor do we recommend a specific wheel for compatibility with our hubs and drums. The wheel manufacturer should be contacted for proof of compatibility before use. Customers using wheels which have not been tested for compatibility must do so to ensure that they are compatible with our hubs and drums. Elements of compatibility include, but are not limited to: ◙ diameter of hub mounting surface

◙ stud diameter and length ◙ location and number of studs

◙ center hole diameter for the wheel

◙ wheel mounting offset from the center rim

◙ rated capacity of the wheel

◙ wheel fastener torque ◙ wheel nut size and shape ◙ use of any wheel accessories (center caps, hub caps, etc.)

Suspension Technology Industries is not responsible for the wheels or rims that are installed on our hubs and drums.

Lug Nut Torque in FT-LBS 5/8”-18 2-Piece Flange Nut 150

Toe and Camber

Toe and camber of the air suspensions are set at the factory prior to shipping. The following information is for reference only. Toe and camber only need to be reset if damage has occurred to the suspensions. Definition of “Toe” Toe is defined as the inward and outward angle of the tires with respect to the front of the vehicle. With toe-in, the front of the tires is closer together than the rear. Toe-out is the opposite.

AXLE TOE(EXAGERATED)

TOP VIEW OF AXLES

FRONT OF VEHICLE FRONT OF VEHICLE

TOE-IN TOE-OUT

Measuring Axle Toe (refer to the diagram on the following page)

1. Set Torque arm assemblies to ride position so that the top of the spindle is parallel to the top of the frame bracket or mounting bracket.

2. Using two straight edges 30 inches in length, mark each straight edge at the center. Hold the straight edges

against a surface known to be perpendicular to the spindle with the center mark at the centerline of the spindle and parallel to the top of the spindle. An acceptable surface is one that was machined to be perpendicular to the spindle centerline.

3. Measure the distance F from the front of one straight edge to the other with respect to the front of the axle and

record the measurement.

4. Measure the distance R from the rear of one straight edge to the other with respect to the front of the axle and record the measurement.

5. Subtract F from R to find the toe. R-F=TOE

a. If TOE is a positive number, the axle is toed-in. b. If TOE is a negative number, the axle is toed-out.

FORWARD

R

F

30"

15" 15"

30"

TOP VIEW OF SUSPENSION

SIDE VIEW OF SUSPENSION

FORWARD

30"

Acceptance Criteria The toe of the axle must be 1/16” TOE-IN, ±1/16” Definition of “Camber” Camber is defined as the inward or outward angle of the tires with respect to vertical. With positive camber, the tops of the tires are farther apart than the bottoms. Negative camber is opposite.

AXLE CAMBER(EXAGERATED)

NEGATIVE CAMBERPOSITIVE CAMBER

(Front View of Axles)

Measuring Axle Camber (refer to the following diagram)

1. Set torque arm assemblies to ride position so that the top of the spindle is parallel to the top of the frame bracket or mounting bracket.

2. Using two straight edges 30 inches in length, mark each straight edge at the center. Hold the straight edges

against a surface known to be perpendicular to the spindle with the center mark at the centerline of the spindle and perpendicular to the top of the spindle. An acceptable surface is one that was machined to be perpendicular to the spindle centerline.

3. Measure the distance T from the top of one straight edge to the other with respect to the front of the axle and

record the measurement.

4. Measure the distance B from the bottom of one straight edge to the other with respect to the front of the axle and record the measurement.

5. Subtract B from T to find the camber. T-B=CAMBER

a. If CAMBER is a positive number, the axle is positively cambered. b. If CAMBER is a negative number, the axle is negatively cambered.

FRONT VIEW OF SUSPENSION

SIDE VIEW OF SUSPENSION

30"

T

B

15"

30"

15"

30"

FORWARD

Acceptance Criteria The camber of the axle must be 1/2” positive camber, ±1/4”

Air Installation Instructions

WARNING ! DO NOT get under trailer without sufficient supports, jack stands, etc., Air suspension may rapidly, suddenly, and without notice lower several inches causing crushing injury and/or death.

Reference the illustration of drawing AK100-019V for a typical layout of airlines, compressor, reservoir tank and air suspensions. The exact configuration will vary depending upon the individual trailer manufacturer’s set-up of the system. Some general suggestions to follow during your air system set-up is as follows:

- Avoid running flexible tubing over any sharp edges. Breaks and cuts will cause air leaks to the system

- After running all air lines, bundle together with zip ties or similar cable wraps

- Avoid sharp cornering or kinking of any air lines

- Do not operate on a low-voltage battery. This will cause damage to the system components. Be sure that your battery is fully charged, or that your charging system is properly working.

- The location of your compressor should be shielded from direct water spray / splash and moisture.

Its location must allow adequate ventilation. It is recommended to be mounted horizontally in length.

Basic Set-Up:

1. If running multiple suspensions (tandem or tri-axle), run air lines between the air spring assemblies in adjacent suspensions. The last fitting outlet of the line is to have a plug inserted in the tee outlet to terminate the air line.

2. The air spring assembly line will feed into the height control valve on the opposite end of the line. It

will be inserted into the “suspension” outlet as shown on drawing LBSGEN-02.

3. Height control valve will need an air lines run between them connecting the two. One height control

valve assembly will require (2) tee fittings to accomplish this. 4. Run an air line from supply outlet tee fitting on the height control valve to the supply outlet on the air

reservoir tank (location “BLUE”).

5. Run an air line from the control outlet tee fitting on the height control valve (location “YELLOW”) to

the supply outlet on the control panel assembly. 6. The last air line is run between the control panel and the air reservoir tank top outlet (location

“RED”).

7. The GREEN and BLACK electrical lines from the control panel are connected to the compressor, and the white wire is to be grounded.

8. The air line of the compressor is run to the intake outlet on the air reservoir tank.

9. Refer to drawing AK100-019V for information regarding thread sealants, wiring connections, and

other specifications.

IF SETTING UP TANDEM OR TRI-AXLE SUSPENSIONS,RUN AIR LINE BETWEEN AIR SPRING ASSEMBLIES

SUSPENSION WITH HEIGHT CONTROL VALVESTO BE PLACED AT THE REAR OF THE TRAILER

RESERVOIR TANK

COMPRESSOR

AIR OPERATIONPANEL ASSEMBLY

1

1

2

2

3

4

5

6

7

8

Control Panel Assembly:

This configuration may vary depending upon the individual trailer manufacturer’s set-up.

SUSPENSION TECHNOLOGY INDUSTRIES

1424 SCALE ST. S.W. CANTON, OHIO 44706PHONE (888) 877-3058 FAX (330) 458-3066

4

TO U

SE SH

RIN

K TU

BIN

G:

1. STR

IP IN

SU

LATIO

N O

N W

IRE BAC

K 3/8".

2. PLA

CE

SH

RIN

K TU

BE OVER

WIR

E.

3. INS

ER

T WIR

E IN

TO TER

MIN

AL.

4. CR

IMP

WIR

E IN

TERM

INAL.

5. SLID

E S

HR

INK

TUBE TO

CO

VER TH

EJO

INT B

ETW

EE

N TH

E WIR

E & THE

TERM

INAL

6. HE

AT TH

E S

HR

INK TU

BE UN

TIL ITS

HR

INKS

AR

OU

ND

THE C

ON

NEC

TION

SE

ALIN

G IT FR

OM

MO

ISTUR

E.

GR

EEN

WIR

E FRO

M P

ANEL

750 CU

IN A

IR R

ESER

VOIR

RE

LAY

TER

MIN

AL D

ES

IGN

ATIO

N

WIR

ES

TO TH

E P

AN

EL M

US

T BE

18 GA

. MIN

. BA

TTERY W

IRES M

UST BE 10 G

A. MIN

.

1/2" SHR

INK

TUBE

SC

HEM

ATIC D

IAGR

AM

10 GA.

-12VDC

BATTE

RY

SEC

TION

A-A

1/4" SHR

INK

TUBE

1/4" SHR

INK

TUBE

1/2" SHR

INK

TUBE

BLA

CK

WIR

E O

N PAN

EL

+12VDC

BATTE

RY

10 GA. S

WIV

EL FITTIN

G

A A

DO

NO

T MO

UN

T EXTE

RN

ALLY

RED

BLA

CK

GR

EEN

YELLO

W

5

GR

OU

ND

RED

CO

MPR

ESSO

R

KN

EE

LING

SIG

NAL LIN

EA

IR P

RE

SS

UR

E P

RE

SEN

T WH

EN KN

EELING

WHITEFR

OM

PAN

EL

87

87a

30

85 86

BR

EAK

ER

YELLO

W

HEIG

HT C

ON

TRO

LV

ALV

E KIT

BLU

E

3

BU

ILT-IN C

HEC

K VALVE

AP

PLY

LIQU

IDTH

REA

D SE

ALANT

INS

ERT PLU

GIN

TO TE

E WH

ENLAS

T FITTING

INTH

E A

IR LIN

E

INS

ER

T PLU

G IN

TO TEE

WH

EN

LAST FITTIN

G IN

THE

AIR

LINE

AK100-019V

CONTINUOUS DUTYCONTROL PANEL

Height Control Valve Initial Adjustment Instructions

WARNING ! DO NOT get under trailer without sufficient supports, jack stands, etc., Air suspension may rapidly, suddenly, and without notice lower several inches causing crushing injury and/or death.

• Note that the air control kit, specifically both of the height control valves, is not set up for operation prior to

leaving the STI factory, and must be done by the trailer manufacturer, trailer dealer, or end user, depending on your circumstances.

• Prior to adjustment, the trailer must be in an unladen (empty) condition with the brakes locked and supported on

a kingpin stand or coupled to a tow vehicle on a flat and level surface. Air must be exhausted from all suspensions on the trailer prior to mounting the trailer on the kingpin stand. The trailer will be in the kneeling position after the air is exhausted.

• Place jacks under the suspension swing arms on the axle equipped with the height control valves. Jack up until

the tires is off of the ground. Remove the tires from this suspension only. Lower the swing arms and remove jacks after the tires are removed.

• Loosen the ¼” adjusting nut connecting the control arm to the adjusting block.

• Place a jack under the hub on each end of the axle.

• Jack the hubs upward until they are at the full “up” position from the downward position. The travel should have

been 5”. Measure from the center of the hub to the ground. Lower the hubs downward 2 ½” from this position. This position is the “design height” of the suspension. Insert the wooden locating pins (included in kit) into the adjustment block and bracket of each height control valve. For your reference, the suspension has approximately 5” of vertical travel, 2 ½” up and 2 ½” down from the design height. See the specifications for your particular suspension.

• Retighten the ¼” lock nuts at the height control valves adjusting block to between 24 – 38 Inch-Lbs.

• Remove the wooden locating pins that were inserted in step #5. Lower and remove jacks from under the hubs

on both ends of the axle. Remount the tires as described in Step #2. Lower and remove jacks under the swing arms.

• Supply air to the suspension’s air system. After five to ten seconds, the trailer should start rising to ride height

and should be level.

Note: This procedure may be done in a work pit without removing the wheels.

INSERT LOCATING PINDURING ADJUST

CURB SIDE HEIGHTCONTROL VALVE ASS'Y.

CONTROL VALVE ASS'Y.DRIVER SIDE HEIGHT

DETAIL "A"

ADJUSTINGBLOCK

1/4" ADJUSTINGLOCK NUT

Re-adjustments to the Height Control Valve to level the trailer

WARNING ! DO NOT get under trailer without sufficient supports, jack stands, etc., Air suspension may rapidly, suddenly, and without notice lower several inches causing crushing injury and/or death.

1. Re-adjusting the height control valves should only be done over a work pit to prevent person injury or death should the trailer suddenly lower. 2. If the trailer is not level, the height control valve on the high side of the trailer may be adjusted by loosening the ¼” lock nut connecting the control arm to the adjusting block. Move the block slightly ± ½” until the trailer is level. Allow five to ten seconds for air to flow in or out of the height control valve due to the time delay built into the valve. This procedure must be done while the suspension system “aired up”. 3. When the trailer is level, re-tighten the ¼” lock nut on the adjusting block.

Operating Instructions

Standard Operating Instructions The daily operation of your air suspension is fairly simple. Refer to the following diagram of the standard STI air operation panel, available as part of the AK100-019V air kit. If you are using a different style or type of air controls, the procedure may vary, but is basically the same as described here. Air-Up Trailer Suspension for Travel

1. Connect the trailer to the tow vehicle, and raise any landing gear or jacks, and remove tire stop blocks. 2. Turn the air compressor switch to the “ON” position. 3. Rotate the “Raise–Lower” valve 180° to the “Raise” position. The lighter side of the trailer may rise faster

than the heavier side. This is normal. 4. Visually check the trailer prior to towing to verify that the trailer is raised and level. 5. You are now ready to pull the trailer. DO NOT turn the compressor off.

Shutting Down Trailer Suspension for Stopping

1. After stopping the tow vehicle, turn the compressor switch to the “Off” position. 2. Rotate the “Raise–Lower” valve 180° to the “Lower” position.

3. If stopping for an extended period, lower landing gear, position jacks, and/or place tire stop blocks.

Suggestions:

1. Lower the trailer and shut “Off” the compressor when parked for extended periods.

2. Always have a trickle charge line from the tow vehicle to the trailer batteries to maintain a charge while towing.

3. If the compressor fails to operate, check the battery charge and ground connection first. Always use

a fully charged battery.

For LBS-SST suspensions without an air source and without height control valves set-up. Installation Instructions

The installation of the LBS-SST will be identical to our LBS suspensions with the exception of not having an air source system to set-up. The LBS-SST suspension is provided with a manual fill bracket assembly which includes a Schrader valve for manually filling the air springs. The bracket assembly can be mounted to the trailer in a location convenient to filling with an outside air source such as an air compressor at a service station or an external air compressor.

Manual Fill Bracket Assembly Your suspension will also be supplied with a length of 1/4” air line for use with the push-in fittings on the suspension and the manual fill valve bracket assembly. Run a length of air line from one side of the tee fitting on your bracket assembly to one of the air springs on the suspension. Run the second length of air line from the other side of the tee fitting to your remaining air spring. Secure all air lines from bracket assembly to air springs with some type of retaining clips. In applications where more than one suspension is being installed on the trailer, use additional tee fittings at the air spring locations to connect the air springs together in series (not supplied). Suspensions being used in a tandem or tri-axle set-up will include two manual fill bracket assemblies. One should be plumbed to supply air to the curb side air springs, and the remaining bracket assembly plumbed to supply air to the driver side air springs. Air supply kits with height control valves are available on the LBS-SST models. This option should be added to the suspension at the time the order is placed.

Air-Up Trailer Suspension for Travel Connect the trailer to the tow vehicle, and raise landing gear or jacks, and remove tire stop blocks if used.

Using the Schrader valve on the manual fill bracket, fill the air springs with air. The total air pressure needed will vary depending on the weight of the trailer and cargo. If additional cargo is added after the initial air-up, you may need to supply the air springs with more air. The amount of air needed will also vary depending upon the desired ride of the trailer. An empty trailer without much weight may only need as little as 10 PSI minimum, whereas a heavier trailer, or trailer loaded with heavier cargo may require 50 PSI maximum. The over-all air pressure required will be dependent upon the user’s personal preference. A good rule of thumb is to measure the frame to ground distance on both sides of the trailer when the air springs are completely empty (trailer must be on level ground). Fill the air springs with air until the trailer rises 1 ¾” on both sides. Another benchmark would be to fill the air springs to a point where the swing arm is horizontal to the ground when the trailer is loaded for use. This provides the optimum suspension utilization. Air pressure can be checked at the Schrader valve with a standard air pressure gauge (not supplied).

Shutting Down Trailer Suspension for Stopping or Storage A dump valve can be added to you air system set-up if you wish to exhaust the air from the air springs when stopping, or when not in use. This is not included with your suspension. If you wish to add a dump valve or other air system components, such as a 12-volt compressor to your LBS-SST suspension system, please contact STI for specifics and pricing.

Suspension Failure During Travel

(Roadside recommendations)

Suspension Failure During Travel

(roadside recommendations)

Loss of air pressure due to break in line or cut in air bag

In the unlikely event you would lose air pressure in the suspension system due to an air line being cut, coming loose from a fitting, or being pinched / crimped, one or more of the airbags will deflate. It is possible to continue to pull the trailer without the air suspension being operable due to the fact that the interior of the airbags contain a rubber cushion.

It is not recommended to pull the trailer any farther than is required to get to a repair facility. Typically a truck repair service center or RV service center is capable of diagnosing the problem and making the repair. Removal of a wheel due to bearing failure In the event of a bearing failure due to lack of lubrication, the removal of the wheel from the trailer may be required in order to continue travel. If the air system is still operable, it will want to inflate the air bag at the location of the missing wheel. In order to continue, you must remove the air line to that specific air bag. The air line must then be crimped shut with either a C-clamp, pair of vice grips, an air line plug, or by folding over and duct taping closed the line. The beam assembly, or “skid plate” under the airbag, must then be secured in order to compress the airbag, and keep the keep the beam from dragging on the roadway. This can be accomplished by using a ratchet binder strap, wrapped from the front of the beam assembly, under the beam, and clamp to the rear of the air bag mounting plate. It is not recommended to pull the trailer any farther than is required to get to a repair facility. Typically a truck repair service center or RV service center is capable of diagnosing the problem and making the repair.

RATCHET BINDER STRAP

COMPRESSAIR BAG

SIDE VIEW OF SUSPENSION

Maintenance

Preventative Maintenance Periodic Check List

Item to check Time Interval Function Required

Suspension System Daily / Pre-Trip Visually inspect suspension for any road-damaged components or any signs of unusual wear at pivot points and trailing beam connection. Check for any signs of tires or suspension components rubbing against the trailer.

Annually Re-torque trailing beam air spring support “U” bolts to factory

specifications. Air System Daily / Pre-Trip Check for sounds of air leaking or the air compressor running

constantly. See Trouble Shooting Guide if there is a problem. Daily / Pre-Trip Drain moisture from air reservoir. Wheels Daily / Pre-Trip Maintain lug nut torque to the wheel manufacturer’s recommendation.

When the trailer is new or a wheel has been removed and reinstalled following the procedures below:

15 miles Check and re-torque lug nuts after the first 15 miles of travel. Re-torque to the wheel manufacturer’s recommendations.

50 miles Check and re-torque lug nuts to the wheel manufacturer’s

recommendations. 100 miles Check and re-torque lug nuts to the wheel manufacturer’s

recommendations. Check lug nut torque periodically after the 100 mile check and re-

torque wheel stud nuts to proper torque. Wheel Bearings Pre-Trip Inspect for any signs of loose hubs. Repack bearings with lubricant

and readjust bearing tightness if bearings are too loose or too tight. Use wheel end manufacturer’s guide lines for torque values.

Daily / Pre-Trip Check for hub grease/oil leaks or seal damage. 100 miles Check wheel and hub area for overheating or lubricant leaking. 1,000 miles Check bearing lock nut adjustment and bearing lubrication. 5,000 miles Check bearing lock nut adjustment and bearing lubrication. 12,000 miles Check bearing lock nut adjustment, clean and repack bearings. Daily / During

Trip Inspect for hubs running hot, inspect hub lubrication and bearing tightness. Repack bearings with lubricant and readjust bearing tightness to manufacturer’s specifications if bearings are too loose or too tight.

Torque Rod Bushings 12,000 Miles Re-grease bushings (4 per axle)

Brakes Every Use Test that brakes are operational. 1,000 miles Check brakes for wear .

Note: Unless your suspension is a Cargo-Max model, your brakes will be either Dexter or Kodiak brand. Refer to the original manufacturer’s manual for specifications and recommendations.

Wheel Bearing Inspection Wash all grease and oil from the bearing cone using a degreaser or similar solvent. Dry the bearing with a clean, lint-free cloth and inspect each roller completely. If there is any sign of pitting, spalling or corrosion, the bearing must be replaced. Typically, replace bearing cups and cones as a set. Wheel Bearing Replacement

WARNING ! Always wear safety glasses when removing or installing force fitted parts. Failure to do so could result in serious eye injury.

1. When replacing the bearing cup, place the hub on a flat surface with the cup to be replaced on the

bottom side.

2. Use a bearing cup driver tool to remove the cup. If a bearing cup driver is not available, you may use a drift punch to tap around the small diameter of the cup until it falls out.

3. After cleaning the hub bore, replace the cup by tapping in with the same tools. Make sure that the

cup is seated all of the way in the hub.

Only replace with bearings as specified in the bearing replacement chart. Wheel Bearing Repacking If available, bearings should be packed by machine. If unavailable, packing by hand is an acceptable method. Pack bearings by placing an amount of grease in the palm of your hand. Press the bearing into the outer edge of the grease, moving it across the pile. Roll the bearing to force grease into the rollers. Continue this process until you have the entire bearing filled with grease. Before reinstalling the bearing, apply a light coat of grease onto the bearing cup mating surface.

(Hand packing a bearing with grease) Wheel Bearing Adjustment The following bearing adjustment and replacement recommendations was developed by TMC’s Wheel End Task Force. It represents the combined input of manufacturers of wheel end components,

1. Bearing Lubrication: Lubricate the wheel bearing with clean lubricant of the same type used in the axle sump or hub assembly.

2. Initial adjusting nut torque: Tighten the adjusting nut to a torque of 200 FT-LBS, while rotating the wheel.

3. Initial back-off: Back the adjusting nut off one full turn.

4. Final adjusting nut torque: Tighten the adjusting nut to a final torque of 50 FT-LBS while rotating the wheel.

5. Final back-off: Back-off the adjusting nut ¼ turn.

6. Jam nut torque: Tighten the jam nut between 200 and 300 FT-LBS for nuts less than Ø2-5/8”, and 300 to 400 FT-

LBS for nuts Ø2-5/8” and over.

7. Acceptable end play: A dial indicator should be attached to the hub or brake drum with its magnetic base. Adjust the dial indicator so that its plunger is against the end of the spindle with its line of action approximately parallel to the axis of the spindle.

Grasp the wheel or hub assembly at the 3 o’clock and 9 o’clock positions. Push and pull the wheel end assembly in and out while oscillating the wheel assembly approximately 45°. Stop oscillating the hub so that the dial indicator tip is in the same position as it was before the oscillation began. Read the bearing end play as the total indicator movement. Acceptable end play is .001” to .005”.

WARNING ! Failure to back off the inner adjusting nut could cause bearing and spindle overheating and/or damage. This could result in the wheel locking up or coming off during operation, and could lead to an accident causing injury or death.

Failure to properly torque the outer jam nut could cause the wheel to come

off during operation, and could lead to an accident causing injury or death.

Typical wheel bearing replacement chart

Brake Size Hub Size

Bearing Race / Cup Part# Cone Part# Kit # Oil / Grease Seal

3.5K Kodiak 10” Disc & Dexter

10” X 2.25”

5-Bolt Inner L68111 L68149 STI # 501019 National #473336 TCM #171255TB

Outer L44610 L44649 5.2K Kodiak 12” Disc & Dexter

12” X 2”

6-Bolt Inner 25520 STI #500788 Dexter #031-030-02

Industry #25580

STI # 500927 National #472920 TCM #22333TBN

Outer 15245 STI #500791 Dexter #031-032-02 Industry #LM67048

Dexter 7K - 12” X 2”

8-bolt Inner Dexter #031-030-01 Industry #25520

STI #500788 Dexter #031-030-02

Industry #25580

Dexter #K71-308-00

STI #500789 Dexter #010-063-00 Nat’l. # 370219BG

Outer Dexter #031-017-03 Industry #14145A

Dexter #031-017-03 Industry #14276

Dexter #K71-310-00

Kodiak 13”

8-bolt Inner Industry #25520 STI #500788 Industry #25580

STI #500789 Nat’l. #370219BG

Outer Industry #14145A STI #500787 Industry #02475

8K - 12 ¼” X 2 ½”

8-bolt Inner Dexter #031-030-01 Industry #25520

STI #500788 Dexter #031-30-02 Industry #25580

Dexter #K71-308-00

STI #500789 Dexter #010-063-00 Nat’l. # 370219BG

Outer Dexter #031-028-01 Industry #02420

STI #500787 Dexter #031-028-02 Industry

#02475

Dexter #K71-415-00

10K – GD Dexter 12 ¼” X 3-3/8”

8-bolt Inner Dexter #031-019-01 Industry #382A

STI #500746 Dexter #031-019-02 Industry #387A

STI #501047 Dexter #010-051-00

Nat’l. #370150 Outer Dexter #031-030-11

Industry #25520 STI #500788

Dexter #031-030-12 Industry #25580

10K – HD Dexter 12 ¼” X 4”

8-bolt Inner Dexter #031-022-01 Industry #394A

STI #500730 Dexter #031-022-02 Industry #395S

STI #500729 Dexter #010-056-00 National #470014

Outer Dexter #031-019-01 Industry #382A

STI #500746 Dexter #031-019-02 Industry #387A

STI Cargo-Max (Timken brand is recommended)

8-bolt Inner STI #501443 Ind. #JM 5119110

STI #501444 Industry #JM 511946

STI #500729 National #370014

Outer STI #501441 Industry #JM 205110

STI #501442 Industry #JM 205149

Brake Pads (see Cargo-Max section for Cargo-Max brake pads) Kodiak Disc Brakes (225 Caliper): Set of 4 pads, STI #502041-1, Industry #D289 Kodiak Disc Brakes (250 Caliper): Set of 4 pads, STI #500802-1, Industry # MKD 215 Dexter Disc Brakes: Set of 4 pads, STI #501725, Dexter #091-004-00 Brake Caliper (see Cargo-Max section for Cargo-Max brake calipers) Kodiak Disc Brakes (225 Caliper): STI #502041, Kodiak # DBC-225-E Kodiak Disc Brakes (250 Caliper): STI #500802, Kodiak # DBC-250-E-SM Dexter Disc Brakes: STI #501624, Dexter #K71-630-00 Bearing Lubrication Grease / Oil should be replaced every 12,000 miles or twelve months. Do not mix Lithium, calcium, sodium, or barium complex greases due to the possibility of contamination problems. Prior to replacement, all old lubrication should be removed from the wheel hub cavity and bearings. Oil replacement should ensure that the oil level is sufficient indicated on the clear plastic oil cap, and can be filled through the rubber plug hole in the cap.

Torque Rod Bushing Lubrication Torque Rod bushings should be re-greased every 12,000 miles or twelve months. Do not mix Lithium, calcium, sodium, or barium complex greases due to the possibility of contamination problems. Fill torque rod housing (four per suspension) with grease thru the grease fitting until it is visibly coming out around the bushings. Recommended Grease Specifications Thickener Type: Lithium Complex Dropping Point: 230°C (446°F) minimum Consistency: NLGI No. 2 Additives: EP, Corrosion & Oxidation Inhibitors Base Oil: Solvent refined petroleum oil Base Oil Viscosity: @40°C (104°F) 150cSt(695 SUS) Minimum Viscosity Index: 80 minimum Pour Point: -10°C (14°F) Minimum Approved Sources Citgo Lithoplex MP NLGI No. 2 Ashland Oil Valvoline Val-Plex EP Grease Exxon/Standard Ronex MP Mobil Oil Mobilgrease HP Kendall Kendall L-427 Penzoil Premium Wheel Bearing Grease Recommended Oil Specifications SAE 90 Hypoid Gear (Hypoid rear axle oil) Note: Only use with hubs equipped with oil lube option. Shell Spirax HD Gear Oil, SAE 80W-90 Exxon Gear Oil GX 80W-90 Union Oil Union MP, Gearlube-LS Mobil Oil Mobilube SHC 75W-90 Pennzoil Multipurpose Gear Lubricant 4092 or 4096 Bearing Seal Inspection and/or Replacement If the hub is removed, inspect the seal to ensure that it has not been nicked, torn, and is still capable of properly sealing the bearing cavity. If there is any doubt, replace the seal. Replace only with seals specified in the bearing replacement chart. To replace the seal, do as follows:

1. Pry the seal out of the hub with a seal puller. It is not recommended to drive the seal out with the inner bearing, as this could cause damage to the bearing and/or seal.

2. Apply a Permatex sealant to the outside of the new seal. 3. Tap the new seal into place using a seal replacer tool. If not available, use a piece of clean, hard wood,

typically a block of wood, to drive the seal into place.

Brakes Standard Brakes: Unless your suspension is a Cargo-Max model, your brakes will be either Dexter or Kodiak brand. Refer to the original manufacturer’s manual for specifications and recommendations regarding operation, maintenance or replacement. Cargo-Max Brakes: Properly installed hydraulic brake systems do not require any special attention with the exception of routine maintenance such as pad replacement. If you do experience problems, it is recommended that the entire tow vehicle and trailer be serviced by a qualified technician. Typical problems occurring in a hydraulic braking system are as follows:

Air in brake lines Faulty brake controller / actuator Water in brake fluid Improper size wires in brake system Air or vacuum leaks Faulty charging system Hydraulic system leaks Rusted or corroded cylinders

A brake line kit is available for the Cargo-Max line of brakes. It is available from Bludot, Inc., telephone number (574) 277-2306, part #1993-001. STI does not supply or install brake line kits. Suspension Technology Industries does not install brake controllers or brake actuators. Refer to the trailer manufacturer’s original operation manual or contact the trailer manufacturer for questions regarding operation or repair to the braking system. Your trailer brakes should be inspected and serviced at yearly intervals, or more often as use requires. When inspecting and removing parts, be certain that all parts removed are replaced in the same brake assembly. Check caliper components for proper operation. Caliper piston(s) must show smooth operation with no signs of sticking. Check rotor for visible gouges or scoring. Minimum rotor thickness is 1.44”. Anything less than this will require rotor replacement. A visual inspection of the brake shoes/pads will tell if they are still usable or not. Replacement of the shoes/pads will be required if worn to less than 1/16”, if contaminated with grease or oil, or if they have visible gouging or scoring. It is important to replace both pads on the brake, as well as turning or replacing both brake rotors on the axle to retain the proper balance of your braking system. Check the shoe/pad sliding freedom front to rear. The proper hold-down clearance is .005” to .010”. Your new brakes should be checked for needed adjustment after the first 200 miles of operation, and every 1,000 miles thereafter. Brake fluid should be checked periodically for the correct level, and for any contamination of dirt, rust, water, etc. Flush and replace if contamination is visible. STI recommends DOT 3 or 4 brake fluid for use in our Cargo-Max brake systems. Periodically inspect wheel or caliper cylinders for proper operation, as well as for any leaks. Brake lines should be checked periodically for cracks, cuts, kinks, or blockage. If needed, flush with fresh brake fluid, and bleed system to remove all air in lines. Replace lines if required.

A Note on using Hydraulic Disc Brakes in an Air-Over-Hydraulic System When using hydraulic disc brakes in an air-over-hydraulic (air/hydraulic) system installed by a trailer manufacturer, dealer or end user, a pressure regulating valve and/or a cross-over valve, such as the Bendix LQ-4, must be installed ahead of the air/hydraulic booster being used. Boosters are typically rated at a 100 PSI supply pressure, yet many truck supply pressures are rated at 120 PSI and above. The resulting output pressure can be so rapid that instantaneous “impact loading” can occur with the brake components. Without the pressure regulation, extremely high hydraulic pressure delivered to the brake components can result in damage to calipers, rotors, brake pads and brackets. Ensure that the final maximum pressure output does not exceed the following:

- 1,200 to 1,300 PSI for 3,500# thru 8,000# axles - 1,500 to 1,600 PSI for 10,000# and 12,000# axles.

Use of a crossover valve installed ahead of the booster, but below the pressure regulating valve, will cut supply pressure by 50% until approximately 70 PSI, and will then “crossover” to a 1:1 ratio. This will make the system similar to an electric/hydraulic system which ramps up hydraulic pressure over a 50 to 100 millisecond time period. Note that an air/hydraulic actuation is not a balanced brake system and excessive brake wear may occur. Additionally, Federal Motor Vehicle Safety Standards (FMVSS) 571.121 requires that all trailers equipped with an air/hydraulic brake system must be equipped with an antilock brake system. This is typically installed on the second axle in a tandem set-up or the third axle in a tri-axle set-up. This was effective as of March 1, 1998. See our “Brake Warranty” page at the back of this manual for warranty details.

Cargo-Max brake caliper and brake pad removal and/or replacement (Brake pad industry #MKD459) It is recommended that you replace all brake pads at the same time to ensure proper brake balance.

1. Turn off all air to suspensions and exhaust the air bags completely. 2. With the trailer connected to a parked and secured tow vehicle, or with the trailer secured to prevent

movement, jack up the trailer. It is recommended to secure trailer with jack stands 3. Remove the wheel from the hub, which will allow you to see the brake assembly. Remove the four bolts

securing the air spring assembly plate (#2 on the typical general assembly diagram in this manual). Disconnect the air line T-fitting (#18) and remove the air spring assembly from the suspension.

4. Disconnect the brake lines from the caliper assembly. The hub and rotor should rotate freely.

5. Remove the two Allen head cap screws from the caliper assembly, allowing it to be removed from the

wheel end kit. One of the hex head cap screws must be removed through an access hole in the adjacent bracket. The brake pads can also be removed at this time, if required. Refer to the following photo for access hole location:

6. Prior to installing or replacing the pads and/or the caliper assembly, take a visual inspection of the rest of the wheel assembly. Check for cracks, sufficient rotor thickness, and inconsistencies in straightness. Replace any parts as needed.

7. Replace the caliper assembly if required. It is recommended to put at least two lug nuts on the wheel

end to secure the hub face to the rotor to ensure proper placement. Remove the lug nuts afterwards.

8. Insert the brake pads into the caliper assembly, and on either side of the rotor. Make sure that the brake lining side of the pads are positioned towards the rotor. Align the spring clips in the pads with the holes in the caliper assembly and secure in place.

9. Apply red Loctite® to caliper bolts and tighten the two Allen head cap screws, torque to between 45

and 55 FT-LBS., and reattach the brake line to the caliper assembly. Reassemble suspension the opposite of step #3.

10. Bleed and flush brake lines.

11. Remount the wheel. Torque lug nuts to 150 FT-LBS. Spin the wheel to ensure proper clearances.

12. BE SURE TO CHECK THAT BRAKES ARE WORKING PROPERLY, PRIOR TO TAKING TRAILER ON ROADWAYS.

ROTOR

CALIPERASSEMBLYBRAKE PADS

(Not shown “as installed”, caliper assembly is vertical, with bleeder on top when installed)

Cargo-Max brake rotor removal and/or replacement It is recommended that you replace all brake pads at the same time to ensure proper brake balance.

1. With the trailer connected to a parked and secured tow vehicle, or with the trailer secured to prevent movement, jack up trailer. It is recommended to secure trailer with jack stands

2. Remove the wheel from the hub, which will allow you to see the brake assembly.

3. Disconnect the brake lines from the caliper assembly. The hub and rotor should rotate freely.

4. Remove the two Allen head cap screws from the caliper assembly, allowing it to be removed from the wheel end kit. One of the hex head cap screws must be removed through an access hole in the adjacent bracket.

5. Prior to installing or replacing the rotor, take a visual inspection of the rest of the wheel assembly.

Check for cracks, sufficient rotor thickness, and inconsistencies in straightness. Replace any parts as needed.

6. Press brake rotor onto the hub, flush with the hub face. Use two lug nuts to secure rotor against the hub

face for help in reinstalling the caliper assembly. After assembly, remove the two lug nuts.

7. Reassemble the caliper assembly onto the caliper bracket. It may be necessary to push the brake pads against the caliper piston to obtain enough clearance to fit the caliper over the rotor.

13. Apply red Loctite® to caliper bolts and tighten the two Allen head cap screws, torque to between 45

and 55 FT-LBS., and reattach the brake line to the caliper assembly. Reassemble suspension the opposite of step #3.

8. Bleed and flush brake lines.

9. Remount the wheel. Torque lug nuts to 105 FT-LBS. Spin the wheel to ensure proper clearances.

10. BE SURE TO CHECK THAT BRAKES ARE WORKING PROPERLY, PRIOR TO TAKING TRAILER

ON ROADWAYS.

Cargo-Max brakes replacement parts Brake pads (set of 4): STI #501802-1; Industry #MKD 459 Caliper: STI #501802-C; Kodiak #338 (curbside) STI #501802-D; Kodiak #338 (driver side) (Must be purchased from Kodiak Trailer Components OR STI due to additional machining required to locate proper bleeder screw location.) Remanufactured calipers may be used by STI if required to meet delivery and demand requirements. All calipers provided by STI carry a one year warranty against defects. Brake pad/shoe replacement is dependent upon usage of the trailer and will vary from owner to owner according to speed, loading, environment, and proper maintenance. Bleeder screw: STI #501802-2 (STI caliper); DBC-NPT-ADP-BBS (Kodiak caliper). Caliper bolts and metal sleeves (2 bolts and 2 sleeves): STI #501802-4; or #H5083 Rubber caliper bolt sleeves (pack of 4 sleeves): STI #501802-5; or #H5788 Caliper repair kit (O-rings and rubber piston boot): STI #501802-6; or #66211

BRAKE PADS, #501802-1

CALIPER BOLTS & METAL

BLEEDER SCREW, #501802-2

SLEEVES, #501802-4

RUBBER SLEEVE, #501802-5

PISTON

CALIPER REBUILDKIT, #501802-6

CARGO-MAX CALIPER ASSEMBLYCOMPLETE WITH ALL SHOWN PARTS

501802-C: CURBSIDE ASSEMBLY501802-D: DRIVER SIDE ASSEMBLY

BRAKE LINE CONNECTOR

Torque Rod Replacement

WARNING ! DO NOT get under trailer without sufficient supports, jack stands, etc., Air suspension may rapidly, suddenly, and without notice lower several inches causing crushing injury and/or death.

1. Before performing any torque rod repair and/or replacement, contact Suspension Technology with the model number and serial number of your suspension(s) for detailed drawing information for your specific suspension. Refer to drawing LBSGEN-02 for general information on your suspension. The repair and/or replacement of a torque rod should only be performed by a qualified technician. 2. If applicable, remove the height control valve from the suspension.

3. Loosen U-bolts (items 19 & 21 on drawing LBSGEN-02). 4. Loosen chain crank (items 6 or 7) from torque rod assembly (item 11 or 12).

5. Loosen beam weldment (item 3) from torque rod assembly.

6. Clean the torque rod removing loose dirt, rust, and grit so that the bushings and seals will not be

damaged when removing the torque rod.

7. Pull the torque rod assembly out of the axle assembly (item 8) in a smooth, straight motion.

8. Thoroughly clean out the bushing housings, removing all grease, grit, rust and any debris.

9. Inspect the seals and bushings in the bushing housings. If they are damaged, replace with STI part numbers 500792 (seal) and 500832 (bushing).

10. If required, insert new U-bolts. New U-bolts are not required provided that the original U-bolts are

not completely disassembled. The torque rod assembly is able to be removed by just loosening the nuts and sliding out the torque rod. If the nuts are removed and the U-bolts taken apart, new U-bolts will be required. Insert new U-bolts through the holes in the chain crank and install one washer (item 17) and one nut (item 16) on each leg of the U-bolts. Engage only 2-3 threads on each nut at this time.

11. Wipe grease onto the entire surface of each bushing to ensure initial lubrication. Any high grade

multi-purpose grease is sufficient.

12. Place one thrust washer (item 1) over the end of the shaft on the torque rod assembly and slide it all of the way down to the spindle arm.

13. Insert the torque rod assembly through the outer bushing in the axle assembly, through the outer U-

bolts, and through the inner bushing.

14. Install another thrust washer between the inner bushing housing and the chain crank (item 6 & 7) before pushing the torque rod through the inner U-bolt (item 19).

15. Slide the torque rod on through the inner U-bolt and chain crank until it stops and there is no gap

between the outer thrust washer, the axle assembly, and the spindle arm.

16. Turn the torque rod assembly until the chain crank registers on the flat notch on the torque rod while keeping the thrust washer tightly against the crank and the inner bushing to eliminate axial travel of the torque rod assembly. Tighten the nuts on the inner U-bolt by hand for now.

17. Register the chain crank on the flat notch on the torque rod. The notch is wider than the chain crank

to allow the chain crank to be located in its most natural position.

18. Place the beam weldment on the torque rod, positioning the beam weldment on the flat notch of the torque rod. Tighten the U-bolts by hand to hold the crank in place.

19. Tighten the U-bolt nuts with an impact wrench first, and then continue to tighten them to 420 FT-

LBS. Note: Too little torque on the nuts will allow damaging movement between the torque rod, beam weldment, and chain crank. Too much torque could cause the U-bolts to fail, causing damage to the wheels and possible loss of vehicle control.

20. Paint all unpainted surfaces to protect from corrosion.

21. Fill both bushing housings with grease until it is visibly coming out around the bushings.

22. Rotate the torque rod assembly to extent of travel to ensure that the grease coats the entire surface.

Do this two to three times. Apply additional grease to the housings if required.

23. If applicable, reinstall the height control valve as shown in the height control valve installation detail shown on drawing LBSGEN-02.

INNER U-BOLT

CHAIN CRANK

HEIGHT CONTROL VALVE

BEAM WELDMENTSPINDLE ARM

TORQUE ROD NOTCH

THRUST WASHER

OUTER U-BOLTS

BUSHING HOUSINGS

TORQUE ROD ASSEMBLY

THRUST WASHER

OUTER BUSHING

M. Powers 6/20/2003

1:8

B

6/23/2003

DE

TAIL A

SC

ALE

1 / 4

HEIG

HT C

ON

TRO

L VALVEIN

STA

LLATION

DE

TAIL

SU

PPPLY

SU

SPEN

SIO

N

CO

NTR

OL

DIS

C BR

AKE

DR

UM

BRAKE

WH

EEL E

ND

KIT

GE

NE

RA

L AS

SE

MB

LYLBS

MO

DELS

NO

TES:

1. WH

EEL E

ND

KITS & TO

RQ

UE

RO

D A

SSEM

BLIES AR

E SHO

WN

FOR

ILLUSTR

ATIO

N P

UR

POSE

S ON

LY. A

CTU

AL PA

RTS M

AY VA

RY

IN AP

PEAR

ANC

E. SEE SPEC

IFICM

OD

EL NU

MBE

R D

RAW

ING

FOR

ACTU

AL PARTS.

2. HEIG

HT C

ON

TRO

L VALV

ES A

RE

SH

OW

N FO

R IN

STA

LLATION

PUR

PO

SES

ON

LY. THEY

AR

E N

OT P

ART O

F THIS BILL O

F MA

TER

IALS. SEE H

EIG

HT C

ON

TRO

L VALVE KITFO

R B

ILL OF M

ATERIA

LS.

3. PO

SITIO

N SP

IND

LES TO

FULL R

EBO

UN

D P

OS

ITION

, PU

LL CH

AINS

OF ITEM

S 6 & 7 TAU

T, AND

WE

LD TO

TUBE

OF ITEM

8.

4. TOE

& C

AMBE

R TO

BE SE

T PER

STI SPEC

1002.

5. INS

TALL W

HE

EL EQ

UIP

ME

NT (IF A

PPLIC

ABLE) P

ER D

EXTE

R O

PER

ATION

MA

INTE

NA

NC

E SER

VIC

E MA

NU

AL. INS

TALL D

ISC

BRAK

ES P

ER K

OD

IAK IN

STALLATION

OPE

RA

TING

INFO

RM

ATIO

N M

ANU

AL.

6. FILL EAC

H TO

RQ

UE R

OD

HO

US

ING

WITH

GR

EAS

E UP

ON

CO

MPLETIO

N.

7. ITEM

S 18 & 20 M

AY B

E SHIP

PED

LOO

SE.

SEE SPECIFIC

MO

DEL N

UM

BER

DR

AW

ING

FOR

BILL O

F MA

TERIA

LS

STA

MP

MO

DEL &

SER

IAL N

UM

BER

S INTH

IS LOC

ATIO

N P

ER S

TI SPE

C 1000

BO

LT TOR

QU

E CH

AR

TS

IZEFT - LBS

3/8 - 165/8 - 113/4 - 16

42022045 *

01

011174

MKP

6/23/0302

1180M

KP6/26/03

0203

1397C

hip3/13/06

03

03* TH

E 3/8"-16 H

EX

HE

AD

CAPSC

REW

S (#14) USED

FOR

ATTA

CH

ING

THE

BEAM

WELD

MEN

T TO TH

EA

IR S

PR

ING

AS

SE

MB

LY H

AVE A MAX. BO

LTTO

RQ

UE

OF 25 FT-LBS.

(SEE TH

E SPEC

IFIC M

OD

EL DR

AW

ING

PR

OVID

ED

WITH

YOU

RS

US

PEN

SIO

N FO

R TH

E EXAC

T SUSP

ENSIO

N C

OM

PON

ENTS)

NO

TE: H

EIG

HT C

ON

TRO

L VALVE ASSEM

BLY (QTY. 2)

NO

T INC

LUD

ED

UN

LESS

OR

DER

ED S

EPAR

ATELY

Storage If your trailer will be stored for an extended length of time, or during the winter months, it is important that the trailer will be properly prepared. Use the following guidelines: 1. If equipped, remove the emergency breakaway battery and store inside at a controlled climate. It is recommended to charge the battery at a minimum of every ninety days. Always verify that the battery is fully charged when used with the trailer, and operating properly. 2. Jack up the trailer and place jack stands under the trailer frame, removing all weight from the tires. Follow the trailer manufacturer’s guidelines to lift and support the unit. Never jack up or place the jack stands on the axle tube. 3. Lubricate all moving parts, including the suspension and hitch, and any moving parts that will exposed to the weather. 4. Boat trailer axles are subject to repeated immersion in water. Prior to storage, remove the brake drums and clean, dry, and re-lubricate all moving brake components and bearings. 5. For oil-lubricated hubs, the upper portion of the bearings are not immersed in oil when in storage, and therefore subject to potential corrosion. For maximum bearing life, it is recommended that you rotate the wheels every few weeks to keep all portions of the bearings lubricated.

6. Prior to being put back into service, inspect the trailer and replace any faulty components. Inspect tires, suspension, wheels and bearings for wear. Remove any dust from braking surfaces. Pre-Trip Checklist Prior to towing your trailer, follow the basic list in ensuring that your trailer is safely functioning. This list should be used prior to every trip, and some items should be checked a few weeks in advance allowing time for any replacement parts or maintenance to be available. 1. Check your trailer’s maintenance schedule to be sure that you are up-to-date. 2. Check the hitch for any wear and that it is properly lubricated. 3. Fasten all safety chains and breakaway switch actuating chain securely. Be certain that the breakaway battery is fully charged. 4. Check all electrical connections for any wear, cuts or loose wires. Be certain lights function properly. 5. Load the trailer so that approximately 10% of the total weight is on the hitch. For light trailers, this can be increased to 15%. Do not overload the trailer & check the trailer’s manual for its rated gross vehicle capacity. 6. Inflate tires according to the manufacturer’s specifications. Inspect for cuts, tears, and wear. 7. Be certain that the brakes are functioning properly. 8. Check that your trailer is being towed in a level position and adjust hitch height if required.

Air Suspension Axle Serial Number Location

Every LBS air suspension that is manufactured by STI has a model number and a serial number stamped in the axle tube, between the height control valve brackets. Additionally, axles produced since 2008 that utilizes an air reservoir tank should have a label mounted on the air tank listing both the model number and serial number(s). By providing STI with either of these numbers when ordering parts or for technical questions, we can greatly expedite the process. STI provides hundreds of combinations of axles, but by providing a serial number, we can determine exactly what suspension you have. Additionally, a serial number is required for any type of warranty. The serial number will be a five digit number, followed by the letter “B”. The model number will start with the letters “LBS”, followed by additional digits, in this format: LBSXX-XXX. The serial and model numbers will not be on a sticker or metal tag, but stamped with 3/8” numbers and letters in the axle tube. Please see the following examples:

Model # & Serial #

Model # & Serial #

Air Tank Label

Air Suspension Components Identification and Definitions

Air Suspension System Components Air Compressor – Continuous Duty style: The air compressor provides

pressurized air to the air suspension system. STI part #550298, Viair 450c part #45040

Air Compressor – General Duty style. This air compressor is a 30% duty cycle. STI part #500691, Viair 275c part #27520

Kneeling Ball Hand Valve: Directs air to and exhausts air from the signal port of the

pilot valves. The valve knob opens and closes the valve. Used to raise and lower the trailer. STI part #550090, SMC Specialty Mfg. Co. #701-4F4F4F

Height Control Valve with integral dump valve: Pilot valves/dump valves control air flow to and from the air springs. Pilot/dump valves are required to allow the trailer to be lowered for loading and unloading, and returning to ride height. The pilot valve requires a signal air pressure from the kneeling valve in order for air to exhaust from the air springs and lower, or kneel, the trailer. #550180 (driver side assembly), #550181 (curb side assembly), 550176 – dump valve portion only, #550118-4 – height control valve with dump valve and air line fittings (Haldex part #905 54 971). (#550143 for valve without dump).

Pilot Valve, stand alone style (if equipped): STI part #550080, Hadley Products #H15162. Used on air systems where the height control valves do not have a built-in dump valve.

Height Control Valve Function

The height control valves are pre-set to control the ride height of the trailer. When the trailer is loaded with weight, it will lower, causing the arms of the height control valves to change position and allow air to flow into the air springs, bringing the trailer up to ride height. When the trailer is unloaded and weight removed, the trailer will rise causing the height control valves to exhaust air from the air springs, bringing the trailer down to ride height. Earlier versions of the LBS suspensions utilized height control valves that were plumbed in conjunction with a pilot valve. This is shown below.

The later versions of the LBS suspensions utilized height control valves that have built-in dump valves, thus doing away with the need for a separate pilot valve, as shown below.

Curb Side

Driver Side

Loosen for adjustment Exhaust

Air line to pilot

Line from air tank

Loosen for adjustment

Driver Side

Driver Side

Curb Side

Exhaust Line

To air spring (green cap)

Line from air tank (blue cap)

Line from raise/lower valve on panel

(yellow cap)

Circuit Breaker: The function of the circuit breaker is to open when the electrical system amperage exceeds 50 amps. This disconnects the circuit to protect the compressor and electrical components. STI part #550174, Shortstop #72175

Electric Relay: The electric relay is operated by the pressure switch. The pressure switch provides low amperage current to the electric relay coil. The high current contacts of the relay then close, providing high amperage current to the compressor. Note: Allowing your battery to run low or go dead will damage electrical components. A fully charged battery will be 14-1/2 volts. Anything less than 12 volts is insufficient and could damage the relay.

STI part #550137, Tyco part #VF4A-45F11-CO1

Pressure Switch: The pressure switch provides electric current to the electric relay coil as required by air pressure. When the air reservoir’s air pressure drops below 105 PSI, the pressure switch contacts close, providing low amperage current to the electric relay. The electric relay contacts then close, providing high amperage current to operate the compressor. The reverse occurs when the air reservoir pressure reaches 120 PSI to turn the air compressor off.

Note: Allowing your battery to run low or go dead will damage electrical components. A fully charged battery will be 14-1/2 volts. Anything less than 12 volts is insufficient and could damage the relay.

. STI part #550153, Nason part #SM-1B-105F/262

Compressor “ON/OFF” Switch: The compressor “ON/OFF” Switch is provided to protect the battery charge from being run down when the trailer is parked for extended periods. STI part #550166, Cole Hersee part #58328-13

Air Spring: The Air Springs support the trailer on an air cushion. The air spring has an internal bumper that supports the trailer should air not be available in the air suspension system. STI part #501296, Goodyear part #2B9-255. (Cross references a Firestone # W01-358-6947).

Check Valve: The Check Valve prevents pressurized air from flowing back through the air compressor when the compressor Is not running. The air flow must be in the direction of the arrow on the valve. STI part #550204, SMC Specialty Mfg. Co. part #410-4M-4M

Pressure Protection Valve: The pressure protection valve will not allow air to flow out of the air reservoir until the reservoir pressure reaches a minimum of 75 PSI. The pressure protection valve closes the line again should the pressure drop below 75 PSI. STI part #550175, Haldex Brake part #N15759DB

Torque Rod Assembly: Consisting of the swing arm, spindle, and torque rod, the torque rod assembly transfers the force from your trailer and wheels to the air spring assemblies. There are various parts numbers depending on the model number of your suspension. Please have suspension model number and/or serial number when ordering replacement. See the “Torque Rod Replacement” section in this manual for additional information. Torque Rod Bushing: Consumable part used with the torque rod assemblies. Two bushings required per torque rod assembly (four total per axle). Per maintenance check list in this manual, should be re-greased every 12,000 miles. STI part #500832. Grease Seal: Consumable part used with the torque rod assemblies. Two seals required per torque rod assembly (four total per axle). Typically are replaced anytime you replace bushings or torque rod assembly. Note: “open” part of seal is placed towards the bushing. STI part #500792. Chicago Rawhide #29840

Trouble-Shooting

Problem Description Possible Cause Solution

Trailer will not rise to normal operating height / air compressor will not turn on.

The compressor “on/off” switch is in the “off” position.

Change compressor switch to “on”. If compressor still does not start, it is possible that the “on/off” switch is faulty. Verify and/or replace.

The kneeling valve is in the wrong

position. Rotate the kneeling valve knob to the correct position, if the valve is not turned completely in the correct position, air will not flow properly. It is possible that the kneeling valve has been plumbed incorrectly. Verify that is has been correctly installed per the Air Installation Instructions.

There is no air pressure and/or the

compressor will not run. Verify that the battery used to power the compressor has the correct charge. Charge or replace battery. Check for any loose wiring connections or corroded connections.

One or more air springs has been

damaged ad is leaking air, or has a leak in an air line.

Visually check air springs and air lines for cuts or abrasions. Replace if damaged.

An air line has an obstruction or

has been crimped. Visually inspect all air lines. Remove any obstructions, straighten any crimps, repair or replace faulty lines.

Faulty pilot valve. If equipped with a pilot valve, it has

not been plumbed correctly or pilot valve is not shifting properly. Verify that the pilot valve has been plumbed per the Air Installation Instructions, and that it is functioning properly when the kneeling valve is turned to the rise or lower position.

Faulty height control valve. Verify that air pressure is being

supplied to the height control valve, as well as coming from the height control valve. Verify that the air lines have not been plumbed backwards. Verify that the guide bolt is attached to the height control valve and is operating freely and is not binding.

Faulty electric relay, circuit breaker,

or pressure switch. Verify that pressure switch, electric relay and/or circuit breaker are functioning. Replace if faulty.

Height Control Valve plumbing Verify lines are plumbed per drawing

Trouble-Shooting (continued)

Problem Description Possible Cause Solution

Trailer will not rise to normal operating height or only one side of trailer will rise.

Any of the same causes for trailer not rising, from previous page.

Same solutions as for trailer not rising, from previous page.

Pilot valve is continuously

exhausting around the head of the valve.

Verify if pilot valve is exhausting around head of valve by using soapy water around the head. Check for air bubbles. The pilot valve spool may be stuck at a centered position. Turn the kneeling valve to the “rise” position to let air pressure build up until the compressor shuts off. Turn the handle back to the “lower” position. This should provide sufficient air pressure to shift the valve spool. If this is a reoccurring problem, clean or replace pilot valve.

Trailer leans to one side, rides too low, or rides too high.

The Height Control Valve needs adjusted.

Review the directions for setting the Height Control Valve height in the Air Installation Instructions. Re-set the height(s).

Air compressor runs continuously. Air system fitting connections may

be leaking. Check by using soapy water at all air line connection fittings. If bubbles appear, there is an air leak. Replace air lines or fittings.

Air pressure relief switch is not

functioning properly. The valve is set to open only at a pressure of 140 PSI or higher. If it is opening prematurely replace the air pressure relief switch.

Electric relay contacts are stuck

open. Replace electric relay.

Pressure switch contacts are stuck

closed. Pressure switch contacts should open between 115 – 125 PSI, stopping the compressor, and should close the contacts between 100-110 PSI, starting the compressor.

Relief valve opens continuously. Check to see if the relief valve has

been installed properly and air flow is entering the correct side of the check valve. If check valve allows any back flow, replace the valve.

Air spring(s) is damaged. Check air spring(s) for cuts or

abrasions. Replace if damaged.

Trouble-Shooting (continued)

Problem Description Possible Cause Solution

Air compressor runs continuously Faulty pressure protection valve. Pressure protection valve could be installed backwards. Verify the proper direction as indicated on the valve. Reinstall valve correctly.

Pressure valve could be plugged. Apply 100 PSI of air pressure to the

“in” port of the valve. If air will not flow through valve at 100 PSI, replace valve.

Air compressor will not run. Faulty pressure switch, electric

relay, or compressor. Connect the compressor directly to a 12 volt battery. Do not connect directly to a battery charger, as the compressor will not function correctly when connected. If the compressor will not run, replace compressor. If it does run, check the pressure switch and electric relay, in that order.

Faulty circuit breaker. Turn the compressor “on/off” switch

to “off” and wait 5 minutes. If the circuit breaker contacts are still open after that time, it is faulty and needs replaced.

Faulty electric relay. Check to see that he electric relay

contacts are opening and closing properly when the pressure switch is operated. Relay contacts should close when the pressure switch supplies current to the relay coil. If the pressure switch is operating properly, disconnect the electric relay providing current to the compressor. If compressor stops running, the electric relay is stuck closed and needs replaced.

Low battery

Verify battery voltage is sufficient.

Air compressor runs for a short time, then stops.

The air compressor thermo-overload switch has opened.

Allow the compressor to cool down. The compressor should start again after the thermo-overload switch has reset. Determine why the compressor is over-heating.

Faulty circuit breaker, or breaker is

not rated for 50 amps. Check the amperage across the compressor terminals, Current should not exceed 35 amps just prior to the compressor shutting off. If the breaker opens at 35 amps, replace with a 50 amp breaker. If it opens at 50 amps, check wiring.

Check valve is plugged. Remove check valve, clean or replace.

Trouble-Shooting (continued)

Problem Description Possible Cause Solution

Electrical wiring is overheating. Improper wire size used. Compressor wiring should be 10 gauge copper minimum. If using a smaller gauge, replace with correct wiring gauge.

The battery that supplies the air compressor discharges continuously.

The compressor “on/off” switch has been left in the “on” position when the trailer is not connected to the tow vehicle, or when the tow vehicle and the trailer have been shut down for an extended period.

Recharge or replace the battery. Always be sure that the compressor switch is in the “off” position when the trailer is disconnected from the tow vehicle for if they are going to be shut down for an extended period of time. If the compressor does not have an “on/off” switch, have one installed.

The battery does not have a charge

line coming from the tow vehicle, or it has been disconnected.

Install, repair, or reconnect the charge line.

Loose or corroded wiring

connections. Clean, tighten, and seal all connections.

Air system bleeds down quickly. Air leak in lines and or fittings. Inspects all air lines and connection

fittings by using soapy water. Air bubbles indicate a leak. Repair or replace faulty air lines or fittings.

Check valve is not holding air

pressure in the air reservoir. Disassemble check valve and apply air pressure to the “out” port. Using soapy water check for air bubbles indicating air flow back through the valve. If any air is allowed back through, replace the faulty valve.

Trailer moves up and down in an excessively jerky movement. Note: The air suspension is an independent wheel suspension. It will rise and lower at different rates side to side. The light side of the trailer will always rise first, and the heavier side will follow. Due to the low air flow rate of a 12-volt compressor, the movement will not always be absolutely smooth.

Axle bushings require lubrication. Charge axle housing grease fittings with grease.

Air system has an air leak. Inspect all air lines, fittings, and components. Use soapy water to verify air leaks. Repair or replace faulty items.

Suspension Record Information

Front Suspension Model #: _____________________________________________________ Serial #: _____________________________________________________ Second Suspension Model #: _____________________________________________________ Serial #: _____________________________________________________ Third Suspension Model #: _____________________________________________________ Serial #: _____________________________________________________ Trailer purchase date: _____________________________________________________ Trailer purchased from: _____________________________________________________ Date trailer put into service: _____________________________________________________ Special equipment notes: _____________________________________________________ _____________________________________________________ _____________________________________________________ _____________________________________________________ Notes / Remarks: _____________________________________________________ _____________________________________________________ _____________________________________________________ _____________________________________________________

1424 Scale St. S.W. Canton, OH 44706 . 330-458-3058 . Fax 330-458-3066 . WWW.RIDETHEAIR.COM

LIMITED WARRANTY “LBS” MODEL SUSPENSION Suspension Technology Industries warrants “LBS” model suspensions furnished by it to be free from structural defects in materials and workmanship under normal use and service for a period of 5 years from the date of sale or installation by the original purchaser, whichever is less. The sole responsibility of Suspension Technology Industries under this warranty is to repair or replace ( without installation ) at the company factory any parts which it manufactures which, within the time schedule described herein shall be returned with transportation charges prepaid ( COD charges will not be accepted ) and which upon examination of returned parts, vehicles, suspension serial numbers and maintenance records, shall be found to be defective. Suspension Technology Industries responsibility shall not exceed the original purchase price of the product claimed to be defective. This warranty does not cover and Suspension Technology Industries makes no warranty with respect to any product that is abused, misused, misapplied, neglected or altered; or that is improperly or incorrectly installed or maintained or used; or that is subject to abnormal conditions of use, temperature, moisture, dirt, or corrosive matter; and any merchandise, materials, parts or components, such as but not limited to, hubs, drums, brakes, bearings, bushings, seals, and air controls, manufactured by someone other than Suspension Technology Industries. Merchandise, material, parts, or components manufactured by someone other than Suspension Technology Industries are warranted to the extent of that manufacture’s warranty to Suspension Technology Industries, or parts only, no labor allowance, 30 days from the trailer date of sale or installation by the original purchaser, which ever is less. Suspension Technology Industries must be notified by the original purchaser with written notice of any breach of the warranty within 30 days after original purchaser or end user, discovers, or should have discovered, the alleged breach. Time is of the essence, and original purchaser’s failure to provide such written notice to Suspension Technology Industries within this 30 day period will fully and completely release Suspension Technology Industries from any obligation or liability for that breach of warranty. This warranty extends only to original purchaser and to no other persons. Suspension Technology Industries must authorize remedies or repairs at a cost determined and approved by Suspension Technology Industries before any remedies or repairs are started. THE WARRANTY HEREIN EXPRESSED SHALL BE THE EXCLUSIVE WARRANTY ON ITEMS MANUFACTURED BY SUSPENSION TECHNOLOGY INDUSTRIES AND SHALL BE IN THE PLACE AND STEAD OF ANY OTHER WARRANTY, EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OR MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE AND IN NO EVENT SHALL SUSPENSION TECHNOLOGY INDUSTRIES BE LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES. Suspension Technology Industries reserves the right to make changes in design and other changes, alterations or improvements to any of its products without this resulting in any obligation upon Suspension Technology Industries to furnish or install the same upon any products previously sold or then in process.

1424 Scale St. S.W. Canton, OH 44706 . 330-458-3058 . Fax 330-458-3066 . WWW.RIDETHEAIR.COM

Warranty Labor Allowance Guidelines

Component / Function Hours covered by STI Warranty Period Air spring 0.7 1 Year (damage caused by road, stones, or Curbs is not covered by warranty) Each additional air spring on same trailer 0.2 Wheel seal, includes removal and 1.0 1 Year remounting hub, drum and tire Wheel bearing, includes removal and 1.0 1 Year remounting hub, drum and tire Brake assembly, includes removal and 1.0 1 Year remounting hub, drum and tire hub and drum/rotor, includes removal and 1.0 1 Year remounting hub, drum and tire Axle assembly / weldment & fabricated parts 3.0 5 Years swing arm assembly / torque rod assembly 2.0 1 Year Swing arm bushings Contact STI 1 Year Axle alignment (toe and camber) Contact STI 1 Year Axle alignment to the trailer 0.0 by others (contact trailer manufacturer) Air compressor 0.0 1 Year Height Control Valve 0.0 30 Days Pilot Valve (if equipped) 0.0 30 Days Circuit breaker 0.0 30 Days Relay 0.0 30 Days Pressure switch 0.0 30 Days The noted labor allowances include technician set-up time, diagnostic time and consideration of applicable supervision / administration requirements. Suspension Technology Industries must authorize and confirm in writing remedies or repairs at a cost determined and approved by Suspension Technology Industries before any remedies or repairs are started. Failure to establish authorization may result in partial or complete loss of warranty coverage. Note: Warranty labor time is estimated. For any items listed or not listed above, the time allowed and labor rate charged must be approved by Suspension Technology Industries and confirmed in writing prior to the work being performed.

Brakes / Wheel End Warranty

Kodiak Trailer Components offers a three year “Parts Only” warranty on their disc brake components. They also offer a “Lifetime Warranty” on their ceramic brake pads. Brake pads must be returned to Kodiak prior to being worn down to the metal backing plate. Kodiak and STI will not warranty any brake pads worn to this extent. Kodiak and STI will not warranty brake calipers, brake rotors or any other braking components damaged due to brake pads being worn to the metal backing plate. Defective parts must be returned for evaluation in order for warranty to occur. A warranty card for Kodiak Trailer Components is inside the Kodiak Trailer Disc Brakes manual included with your “End User Information Pack”, and must be filled out and returned to Kodiak in order for any warranty to be valid. The initial one year of parts and labor are covered by STI’s warranty, and the balance of two years will be “Parts Only” by Kodiak, with the end user contacting Kodiak direct. Inquiries can be made to Kodiak at (800) 756-3425. Dexter Axle offers a two year limited warranty on their brake components. Dexter does not cover normal wear and tear, and is limited to the original purchaser. The initial one year of parts and labor are covered by STI’s warranty, and the balance of two years will be by Dexter Axle, with the end user contacting Dexter Axle direct at (574) 295-8094. Suspension Technology Industries warranties the Cargo-Max brake components for parts and labor for one year from date of purchase. Caliper only has an additional “Parts Only” warranty from Kodiak Trailer Components for an additional two years. Ceramic brake pads have a “Lifetime Warranty”. Brake pads must be returned to Kodiak prior to being worn down to the metal backing plate. Kodiak and STI will not warranty any brake pads worn to this extent. Kodiak and STI will not warranty brake calipers, brake rotors or any other braking components damaged due to brake pads being worn to the metal backing plate. Defective parts must be returned for evaluation in order for warranty to occur. Note that warranty parts are shipped as standard via UPS—Ground service. Requests for overnight shipments must be prepaid with a credit card, or using a purchase order for existing credit accounts.

Warranty Procedure Guide

Making a claim:

Review the Suspension Technology, Ind. Warranty statement for the product in question. If the components are within the stated coverage time period, continue… All claims must be processed by the original manufacturer or purchaser. Record the following information: Suspension Technology, Ind. Suspension model # and serial #’s (note: the serial numbers will be stamped on the main axle tube). Type of trailer and trailer manufacturer. Trailer In-service date. Part number and description of the failed or problem component.

Warranty starting date:

The starting date shall be determined by the date of sale or installation by the original purchaser, whichever is less. Major structural component warranty:

The major structural component warranty covers any failure of a major structural component manufactured by Suspension Technology, Ind. Which occurs under normal use and is the result of defects in material and workmanship.

Vendors warranty:

If the equipment includes components supplied by others, Suspension Technology, Ind. Will, to the extent allowed, pass along to the purchaser any warranty provided by the manufacturer of the component. Electrical components and valves are covered for parts only, no labor, for a period of 30 days from the date specified as Warranty Starting Date.

Returned Goods Policy / Warranty Policy – The following items are required when submitting a claim for warranty or returning an item:

1. Call for a claim number @ 330-458-3058. This claim number must be referenced on all correspondence, including packing list and all follow-up documentation.

2. Completed Form – Required information on the form is Order Number or Invoice Number, or Serial Number of Suspension(s). A valid reason must be given in writing for warranty claims.

3. A copy of your “in house” service report form. This form is not required, but will help to expedite the processing of your warranty claim. The form should provide pertinent information needed in evaluating the claim.

4. Mark clearly on one side of the package the claim number. 5. Return the item(s) within 10 days from the issuance of the claim number (claims with no items returned, exceeding 30 days,

will automatically be closed without notification). Please allow approximately two weeks for evaluation and determination of claim.

6. Replacement item(s) can be requested when filing a claim, however, replacement parts will be invoiced, including freight. Credit for the replacement item(s) will be dependent upon the evaluation and determination of claim. Freight will be credited for standard delivery service only.

7. Vendor Evaluation Fees may be charged / invoiced if no problems are detected by STI personnel and the customer requests, in writing, that the item(s) in question be returned to the original manufacturer for evaluation per Vendor’s warranty guidelines.

8. Warranty work cannot begin until Suspension Technology, Ind. (STI) issues a written approval for parts replacement, repairs, and/or labor allowance if applicable.

1424 Scale St. S.W. Canton, OH 44706 . 330-458-3058 . Fax 330-458-3066 . WWW.RIDETHEAIR.COM

Return Authorization Form

Claim Number ____________________ Your reference number _______________________ (call 330-458-3058 for this number) Your P.O. number __________________________________ Date returned _____________________ Your Company: ___________________________________________________________________________ Contact Name: ____________________________________________________________________________ Address: _________________________________________________________________________________ Telephone: ____________________ Fax: _________________ E-Mail: ____________________________ Return equipment to (if different address or company): _________________________________________________________________________________________ Additional notes / remarks: __________________________________________________________________ _________________________________________________________________________________________

Description of equipment / part being returned, along with serial number:

1. __________________________________________________ Serial # _____________________ 2. __________________________________________________ Serial # _____________________ 3. __________________________________________________ Serial # _____________________ 4. __________________________________________________ Serial # _____________________

Reason for Return:

1. _______________________________________________________________________________ 2. _______________________________________________________________________________ 3. _______________________________________________________________________________

i. _______________________________________________________________________________

STI USE ONLY Date Received: ________________________ By: ___________________________________ Comments: _____________________________________________________________________

Return this form to the following address / fax. Retain a copy for your records.

1424 Scale St. S.W. Canton, OH 44706 . 330-458-3058 . Fax 330-458-3066 . WWW.RIDETHEAIR.COM

Parts Availability and Ordering Procedure BUSINESS HOURS Monday - Friday 8:00 a.m. to 5:00 p.m. (Eastern Standard Time) UPS shipments: Cut-off time for same-day parts shipment - 3:00 P.M. EST FREIGHT TERMS Suspension parts, etc., are shipped* pre-paid and add UPS-Ground unless otherwise requested. Suspensions are shipped* pre-paid and add “best way” unless a specific carrier is requested for “collect” delivery. *subject to credit approval Complete suspension shipments must go via Common Carrier Freight. Note: “Next Day” shipments outside of the United States may not be possible due to shipping constraints and customs requirements. STI attempts to keep a complete inventory of all possible replacement parts. Occasionally, a purchased part or assembly (such as wheel end equipment) will be needed to be ordered from the vendor. Delivery time will be dependent upon the vendor’s inventory and delivery. Complete torque rod assemblies are generally not kept in stock due to the various specifications for each particular suspension. A minimum of four hours will be needed when ordering torque rod assemblies in order to heat, press, and allow assemblies to cool. Note that warranty parts are shipped as standard via UPS—Ground service. Requests for overnight shipments must be prepaid with a credit card, or using a purchase order for existing credit accounts.

Credit Policy and Terms

An “Open Account” must be established before we can ship any merchandise. Applications for credit are available from our credit department. Our terms of conditions are net 30 days from invoice date unless otherwise agreed. In the event payment is not

made when due, buyer agrees to pay seller a service charge of 1-1/2% (1.5%) per month (18% per annum) on the unpaid balance of the invoice from the invoice date.

VISA, MasterCard, Discover and American Express are accepted for payment. Credit card orders must be

placed by 3:00 P.M. EST to ship that day. C.O.D. shipments are available. Additional costs will incur.

Suspension Technology, Ind. 1424 Scale Street S.W.

Canton, OH 44706 Tel: 888-877-3058 Fax: 330-458-3066

WWW.RIDETHEAIR.COM