95ZJ_3.PDF

REAR SUSPENSION AND AXLES

CONTENTS

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AXLE NOISE/VIBRATION DIAGNOSIS . . . . . . . . . 6AXLE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . 32GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1MODEL 35 AXLE . . . . . . . . . . . . . . . . . . . . . . . . 10

REAR SUSPENSION . . . . . . . . . . . . . . . . . . . . . . 3TORQUE SPECIFICATIONS . . . . . . . . . . . . . . . . 32TRAC-LOK DIFFERENTIAL . . . . . . . . . . . . . . . . . 27

GENERAL INFORMATION

REAR SUSPENSIONThe Grand Cherokee rear suspension is link/coil

design comprised of (Fig. 1);• Drive axle• Coil springs• Upper and lower suspension arms• Dual-action shock absorbers• Track bar• Stabilizer bar• Jounce bumpers

The upper and lower suspension arms use bushingsto isolate road noise. The suspension arms are boltedto the body and axle through the rubber bushings.The upper suspension arm has provision for the useof cam bolts at the axle to allow for pinion angle orthrust angle adjustment. The cams are available as aservice kit and are not installed at the factory. Thesuspension arm travel is limited through the of usejounce bumpers in compression and shock absorbersin rebound.

Suspension components which use rubber bushingsshould be tightened at vehicle ride height. This willprevent premature failure of the bushing and main-tain ride comfort. Bushings must never be lubricated.

The coil springs mount up in the fender shield thatis part of the unitized body bracket. There is a rub-ber isolator between the top of the spring andbracket to isolate road noise. The bottom of thespring seats on the axle pad and is retained with aclip.

The shock absorbers dampen jounce and rebound ofthe vehicle over various road conditions. The top ofthe shock absorbers are bolted to the body. The bot-tom of the shocks are bolted to the axle shock ab-sorber bracket.

The stabilizer bar is used to control vehicle bodyroll during turns. The spring steel bar helps to equal-ize the vehicle body in relationship to the suspension.The bar extends across the underside of the chassisand connects to the frame rails. Links are connectedfrom the bar to the axle brackets. Stabilizer bar areisolated by rubber bushings.

The track bar is used to control rear axle lateralmovement. The track bar is attached to a frame railbracket and an axle bracket. It is isolated with bush-ings at both ends.

REAR AXLEThe integral housing, hypoid design has the pinion

set below the ring gear.Fig. 1 Rear Suspension

ZJ REAR SUSPENSION AND AXLES 3 - 1

The axles are equipped with A.B.S. brake systems.The A.B.S. tone rings are pressed onto the axle shaftnear the hub flange. For additional information onthe A.B.S. system refer to Group 5, Brakes.

The Model 35 axle has the assembly part numberand gear ratio listed on a tag. The tag is attached tothe housing cover (Fig. 2). Build date identificationcodes are stamped on the axle shaft tube cover side.

The Model 35 axle is available with Trac-Lok™(limited slip) differential as an option.

STANDARD DIFFERENTIAL OPERATIONThe differential gear system divides the torque be-

tween the axle shafts. It allows the axle shafts to ro-tate at different speeds when turning corners.

Each differential side gear is splined to an axleshaft. The pinion gears are mounted on a pinionmate shaft and are free to rotate on the shaft. Thepinion gear is fitted in a bore in the differential caseand is positioned at a right angle to the axle shafts.

In operation, power flow occurs as follows:• Pinion gear rotates the ring gear• Ring gear (bolted to the differential case) rotatesthe case• Differential pinion gears (mounted on the pinionmate shaft in the case) rotate the side gears• Side gears (splined to the axle shafts) rotate theshafts

During straight ahead driving, the differential pin-ion gears do not rotate on the pinion mate shaft. Thisoccurs because input torque applied to the gears isdivided and distributed equally between the two sidegears. As a result, the pinion gears revolve with thepinion mate shaft but do not rotate around it (Fig. 3).

When turning corners, the outside wheel must

travel a greater distance than the inside wheel in or-der to complete a turn. This difference must be com-pensated for in order to prevent the wheels fromscuffing and skidding through the turn. To accom-plish this, the differential allows the axle shafts toturn at unequal speeds (Fig. 4). In this instance, theinput torque applied to the pinion gears is not di-vided equally. The pinion gears now rotate aroundthe pinion mate shaft in opposite directions. This al-lows the side gear and axle shaft attached to the out-side wheel to rotate at a faster speed.

Fig. 2 Model 35 Differential Cover

Fig. 3 Differential Operation—Straight-Ahead Driving

Fig. 4 Differential Operation—On Turns

3 - 2 REAR SUSPENSION AND AXLES ZJ

REAR SUSPENSION

INDEX

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Coil Spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Lower Suspension Arm . . . . . . . . . . . . . . . . . . . . . . 4Service Information . . . . . . . . . . . . . . . . . . . . . . . . . 3Shock Absorber . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Spring and Shock Diagnosis . . . . . . . . . . . . . . . . . . 4Stabilizer Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Track Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Upper Suspension Arm . . . . . . . . . . . . . . . . . . . . . . 4

SERVICE INFORMATION

CAUTION: Suspension components that use rubberbushings should be tightened with the vehicle atnormal ride height. If the springs are not at theirnormal ride position, vehicle ride comfort and han-dling could be affected. Rubber bushings mustnever be lubricated.

TRACK BAR

REMOVAL(1) Raise and support the vehicle.(2) Remove the bolt and nut from the frame rail

bracket (Fig. 1).

(3) Remove the bolt from the axle tube bracket(Fig. 1). Remove the track bar.

INSTALLATION(1) Install the track bar to the axle bracket and in-

stall a new bolt (Fig. 1).

(2) It may be necessary to pry the axle assemblyover to install the track bar. Install the track bar tothe frame rail bracket. Loosely install the bolt andflag nut (Fig. 1).

(3) Remove the supports and lower the vehicle.(4) Tighten the track bar bolts 100 Nzm (74 ft. lbs.)

torque.

STABILIZER BAR

REMOVAL(1) Raise and support the vehicle. Remove one

wheel and tire.(2) Disconnect the stabilizer bar links from the

axle brackets (Fig. 2).(3) Lower the exhaust by disconnecting the muffler

and tail pipe hangers.(4) Disconnect the stabilizer bar from the links.(5) Disconnect the stabilizer bar clamps from the

frame rails. Remove the stabilizer bar.

Fig. 1 Rear Track Bar

Fig. 2 Rear Stabilizer Bar


INSTALLATION(1) Position the stabilizer bar on the frame rail and

install the clamps and bolts. Ensure the bar is cen-tered with equal spacing on both sides. Tighten thebolts to 54 Nzm (40 ft. lbs.).

(2) Install the links and grommets onto the stabi-lizer bar and axle brackets (Fig. 2). Install the nutsand tighten to 36 Nzm (27 ft. lbs.) torque.

(3) Connect the muffler and tail pipe to their hang-ers.

(4) Install the wheel and tire.

UPPER SUSPENSION ARM

REMOVAL(1) Raise and support the vehicle.(2) Remove the upper suspension arm nut and bolt

at the axle bracket (Fig. 3). Remove the ABS wirebracket from the arm.

(3) Remove the nut and bolt (Fig. 3) at the framerail and remove the upper suspension arm.

INSTALLATION(1) Position the upper suspension arm at the axle

and frame rail (Fig. 3).(2) Install the bolts and finger tighten the nuts

(Fig. 3). Install the ABS wire bracket onto the arm.(3) Remove the supports and lower the vehicle.(4) Tighten the upper suspension arm nuts to 75

Nzm (55 ft. lbs.) torque.

LOWER SUSPENSION ARM

REMOVAL(1) Raise and support the vehicle.

(2) Remove the lower suspension arm nut and boltat the axle bracket (Fig. 3).

(3) Remove the nut and bolt (Fig. 3) at the framerail and remove the lower suspension arm.

INSTALLATION(1) Position the lower suspension arm at the axle

bracket and frame rail bracket (Fig. 3).(2) Install the bolts and finger tighten the nuts

(Fig. 3).(3) Remove the supports and lower the vehicle.(4) Tighten the lower suspension arm nuts to 177

Nzm (130 ft. lbs.) torque.

SPRING AND SHOCK DIAGNOSISA squeak noise from the shock absorber can be pro-

duced if movement between the rubber bushings andthe metal occurs. This noise can usually be correctedby tightening the attachment nuts. If the squeaknoise persists, inspect for damaged and worn bush-ings, and attaching components. Repair as necessary.

The shock absorbers are not refillable or adjust-able. If a malfunction occurs, the shock absorbermust be replaced. To test a shock absorber, hold it inan upright position and force the piston into and outof the cylinder four or five times. The action through-out each stroke should be smooth and even.

SHOCK ABSORBER

REMOVAL(1) Raise and support the vehicle. Position a hy-

draulic jack under the axle to support it.(2) Remove the upper nut and retainer from the

frame rail stud (Fig. 4).(3) Remove the lower nut and bolt from the axle

bracket. Remove the shock absorber.

INSTALLATION(1) Install the shock absorber on the upper frame

rail stud. Install the shock absorber on the axlebracket (Fig. 4).

(2) Install the retainer and nut on the stud.Tighten the upper nut to 70 Nzm (52 ft. lbs.) torque.

(3) Tighten the lower nut to 92 Nzm (68 ft. lbs.)torque.

(4) Remove the supports and lower the vehicle.

COIL SPRING

REMOVAL(1) Raise and support the vehicle. Position a hy-

draulic jack under the axle to support it.(2) Disconnect the stabilizer bar link and shock ab-

sorber from the axle bracket.(3) Disconnect the track bar from the frame rail

bracket.

Fig. 3 Upper and Lower Suspension Arms


(4) Lower the axle until the spring is free from theupper mount seat. Remove the coil spring retainerbolt (Fig. 4) and remove the spring.

INSTALLATIONInspect isolator the for damage or wear. Replace

the isolator if necessary before installing spring.(1) Position the coil spring on the axle pad. Install

the spring retainer and bolt (Fig. 4). Tighten the boltto 22 Nzm (16 ft. lbs.) torque.

(2) Raise the axle into position until the springseats in the upper mount.

(3) Connect the stabilizer bar links and shock ab-sorbers to the axle bracket. Connect the track bar tothe frame rail bracket.

(4) Remove the supports and lower the vehicle.

Fig. 4 Rear Coil Spring & Shock Absorber


AXLE NOISE/VIBRATION DIAGNOSIS

INDEX

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Driveline Snap . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Gear and Bearing Noise . . . . . . . . . . . . . . . . . . . . . 6General Information . . . . . . . . . . . . . . . . . . . . . . . . 6Limited Slip Differential . . . . . . . . . . . . . . . . . . . . . . 7

Low Speed Knock . . . . . . . . . . . . . . . . . . . . . . . . . . 7Rear Axle Alignment . . . . . . . . . . . . . . . . . . . . . . . . 7Vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

GENERAL INFORMATIONAxle bearing problem conditions are usually caused

by:• Insufficient or incorrect lubricant• Foreign matter/water contamination• Incorrect bearing preload torque adjustment

When serviced, the bearings must be cleaned thor-oughly. They should be dried with lint free shop tow-els. Never spin bearings with compressed air.This will overheat them and brinell the bearingsurfaces. This will result in noisy operation af-ter repair.

Axle gear problem conditions are usually the resultof:• Insufficient lubrication• Incorrect or contaminated lubricant (water)• Overloading (excessive engine torque)• Incorrect clearance or backlash adjustment

Insufficient lubrication is usually the result of ahousing cover leak. It can also be from worn axleshaft or pinion gear seals. Check for cracks or porousareas in the housing or tubes.

Using the wrong lubricant will cause overheatingand gear failure. Gear tooth cracking and bearingspalling are indicators of this.

Axle component breakage is most often the resultof:• Severe overloading• Insufficient lubricant• Incorrect lubricant• Improperly tightened components

Common causes of overloading is from full throttleacceleration. Overloading happens when towingheavier than recommended loads. Component break-age can occur when the wheels are spun excessively.Insufficient or incorrect lubricants contribute tobreakage through overheating. Loose differentialcomponents can also cause breakage.

Incorrect bearing preload or gear backlash will notresult in component breakage. Mis-adjustment willproduce enough noise to cause service repair before afailure occurs. If a mis-adjustment condition is notcorrected, component failure can result.

GEAR AND BEARING NOISE

GEAR NOISEAxle gear noise can be caused by insufficient lubri-

cant. Incorrect backlash, tooth contact, or worn/dam-aged gears can cause noise.

Gear noise usually happens at a specific speedrange. The range is 30 to 40 mph, or above 50 mph.The noise can also occur during a specific type ofdriving condition. These conditions are acceleration,deceleration, coast, or constant load.

When road testing, accelerate the vehicle to thespeed range where the noise is the greatest. Shift outof gear and coast through the peak noise range. Ifthe noise stops or changes greatly, check for insuffi-cient lubricant. Incorrect ring gear backlash, or geardamage can cause noise changes.

Differential side and pinion gears can be checkedby turning the vehicle. They usually do not causenoise in straight ahead driving. These gears areloaded during vehicle turns. If noise does occur dur-ing vehicle turns, the side or pinion gears could beworn or damaged. A worn pinion gear mate shaft canalso cause a snapping or a knocking noise.

BEARING NOISEThe axle shaft, differential and pinion gear bear-

ings can all produce noise when worn or damaged.Bearing noise can be either a whining, or a growlingsound.

Pinion gear bearings have a constant pitch noise.This noise changes only with vehicle speed. Pinionbearing noise will be higher because it rotates at afaster rate. Drive the vehicle and load the differen-tial. If bearing noise occurs the pinion rear bearing isthe source of the noise. If the bearing noise is heardduring a coast, front bearing is the source.

Worn, damaged differential bearings usually pro-duce a low pitch noise. Differential bearing noise issimilar to pinion bearing. The pitch of differentialbearing noise is also constant and varies only withvehicle speed.

Axle shaft bearings produce noise and vibrationwhen worn or damaged. The noise generally changeswhen the bearings are loaded. Road test the vehicle.Turn the vehicle sharply to the left and to the right.


This will load the bearings and change the noiselevel. Where axle bearing damage is slight, the noiseis usually not noticeable at speeds above 30 mph.

LOW SPEED KNOCKLow speed knock is generally caused by a worn

U-joint or by worn side gear thrust washers. A wornpinion gear shaft bore will also cause low speed knock.

VIBRATIONVibration at the rear of the vehicle is usually

caused by a:• Damaged drive shaft• Missing drive shaft balance weight• Worn, out-of-balance wheels• Loose wheel lug nuts• Worn U-joint• Loose spring U-bolts• Loose/broken springs• Damaged axle shaft bearings• Loose pinion gear nut• Excessive pinion yoke run out• Bent axle shaft

Check for loose or damaged front end componentsor engine/transmission mounts. These componentscan contribute to what appears to be a rear end vi-bration. Do not overlook engine accessories, bracketsand drive belts.

All driveline components should be examined be-fore starting any repair.

Refer to Group 22, Wheels and Tires for additionalinformation.

DRIVELINE SNAPA snap or clunk noise when the vehicle is shifted

into gear (or the clutch engaged), can be caused by:• High engine idle speed• Loose engine/transmission/transfer case mounts• Worn U-joints• Loose spring mounts• Loose pinion gear nut and yoke• Excessive ring gear backlash• Excessive differential side gear to case clearance

The source of a snap or a clunk noise can be deter-mined with the assistance of a helper. Raise the ve-hicle on a hoist with the wheels free to rotate.Instruct the helper to shift the transmission intogear. Listen for the noise, a mechanics stethoscope ishelpful in isolating the source of a noise.

REAR AXLE ALIGNMENT

MEASUREMENTThe following procedure can be used to determine

if abnormal rear tire tread wear is the result of abent or deformed rear axle shaft.

(1) Raise both rear wheels off the surface with aframe contact hoist.

(2) Attach a one inch long piece of masking tape atthe center of each tire tread for use as reference marks.

(3) Rotate the rear wheels until both referencemarks face the front of the vehicle. Measure the dis-tance between the outside edges of the two pieces oftape. Record this measurement as the front of tire(FTR) measurement.

(4) Rotate the rear wheels until both referencemarks face the rear of the vehicle. Measure the dis-tance between the outside edges of the two pieces oftape. Record this measurement as the rear of tire(RTR) measurement.

(5) Subtract the (RTR) measurement from the(FTR) measurement to obtain the amount of wheeltoe. The acceptable rear wheel toe-in position is 1/16inch (1.6 mm) to 3/16 inch (4.8 mm) toe-out.

(6) Rotate the rear wheels until the referencemarks are facing downward. Measure the distancebetween the outside edges of the two pieces of tape.Record this measurement as the bottom of tire (BTR)measurement.

(7) Average the (FTR) and the (RTR) distance mea-surements. Subtract the (BTR) measurement fromthis average distance to obtain the camber. The ac-ceptable amount of camber is 1/16 inch to 3/32 inch(1.6 to 2.4 mm).

(FTR + RTR) DIVIDED BY 2 (TWO) MINUSBTR EQUALS CAMBER

If the (BTR) distance measurement is lessthan the average FTR and RTR distance mea-surement, the camber will be positive ( + ). Ifthe (BTR) distance measurement is greaterthan the average FTR and RTR distance, thecamber will be negative ( - ).

If the toe position or camber is not acceptable, abent or deformed rear axle shaft is most likely thecause.

LIMITED SLIP DIFFERENTIALUnder normal traction conditions, engine torque is

divided evenly. With low traction surfaces, enginetorque is transferred to the wheel with the most tiretraction. When diagnosing a limited-slip differentialproblem condition, the wheel with the least tractioncan continue spinning.

The most common problem is a chatter noise whenturning corners. Check for incorrect or contaminatedlubricant. Replace the gear lubricant if necessary.• With Trac-Lok differentials add a container ofMOPARt Trac-Lok Lubricant.

This will correct the condition in most instances. Ifthe chatter persists, clutch damage could have occurred.

After changing the lubricant, drive the vehicle andmake 10 to 12 slow, figure eight turns. This maneu-ver will pump lubricant through the clutches.


SERVICE DIAGNOSIS


SERVICE DIAGNOSIS (CONT’D)


MODEL 35 AXLE

INDEX

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Axle Assembly Replacement . . . . . . . . . . . . . . . . . 10Axle Shaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Axle Shaft Seal and Bearing . . . . . . . . . . . . . . . . . 13Backlash and Contact Pattern Analysis . . . . . . . . . 23Cleaning/Inspection . . . . . . . . . . . . . . . . . . . . . . . . 16Differential Assembly . . . . . . . . . . . . . . . . . . . . . . . 17Differential Disassembly . . . . . . . . . . . . . . . . . . . . 14Differential Measurement and Installation . . . . . . . . 21Differential Removal . . . . . . . . . . . . . . . . . . . . . . . 14

Final Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . 26General Information . . . . . . . . . . . . . . . . . . . . . . . 10Lubricant Change . . . . . . . . . . . . . . . . . . . . . . . . . 11Lubricant Specifications . . . . . . . . . . . . . . . . . . . . . 10Pinion Gear Depth Information . . . . . . . . . . . . . . . 17Pinion Measurement and Assembly . . . . . . . . . . . . 19Pinion Removal/Disassembly . . . . . . . . . . . . . . . . . 15Pinion Shaft Seal Replacement . . . . . . . . . . . . . . . 11

GENERAL INFORMATIONThe housing for Model 35 rear axles consists of an

iron center casting with tubes extending from eitherside. The tubes are pressed into and welded to thedifferential housing to form a one piece axle housing.

The integral type housing, hypoid gear design hasthe centerline of the pinion set below the centerlineof the ring gear.

The axle has a fitting for a vent hose used to re-lieve internal pressure caused by lubricant vaporiza-tion and internal expansion.

The axles are equipped with semi-floating axleshafts, meaning that loads are supported by the axleshaft and bearings. The axle shafts are retained byC-clips in the differential side gears.

The axles are equipped with ABS brake sensors.The sensors are attached to the brake backing plateassemblies and tone rings are pressed on the axleshaft. Use care when removing axle shafts as NOT todamage the tone wheel or the sensor.

The removable cover provides a means for servicingthe differential without removing the axle assembly.

The Model 35 axle has the assembly part numberand gear ratio listed on a tag. The tag is attached tothe housing cover. Build date identification codes arestamped on the axle shaft tube cover side.

The differential case is a one piece design. The dif-ferential pinion mate shaft is retained with athreaded roll pin. Differential bearing preload andring gear backlash is adjusted by the use of spacershims. The shims are located between the differentialbearing cups and housing. Pinion bearing preload isset and maintained by the use of a collapsible spacer.

For complete drive axle assembly removaland installation refer to Drive Axle AssemblyReplacement in this Group.

LUBRICANT SPECIFICATIONSMulti-purpose, hypoid gear lubricant should be

used for Model 35 axle. The lubricant should have

MIL-L-2105C and API GL 5 quality specifications.MOPARt Hypoid Gear Lubricant conforms to both ofthese specifications.• Lubricant for standard Model 35 axle use ther-mally stable SAE 80W-90 gear lubricant.• Lubricant for Model 35 axle with Trailer Tow useSAE 75W-140 SYNTHETIC gear lubricant.• Trac-Lok (limited slip) differentials add 4 fluid oz.of friction modifier.• The lubricant quantity is 5661 fluid oz..

Refer to Group 0, Lubrication and Maintenance foradditional information.

CAUTION: If axle is submerged in water, lubricantmust be replaced immediately to avoid possiblepremature axle failure.

AXLE ASSEMBLY REPLACEMENT

REMOVAL(1) Raise and support the vehicle.(2) Position a floor jack under the axle.(3) Remove the wheels and tires. Remove the

brake components from the axle, refer to Group 5,Brakes.

(4) Disconnect the vent hose from the axle shafttube.

(5) Mark the propeller shaft and yokes for installa-tion alignment reference. Remove the propeller shaft.

(6) Disconnect stabilizer bar links.(7) Disconnect shock absorbers from axle.(8) Disconnect track bar.(9) Disconnect upper and lower suspension arms

from the axle brackets.(10) Lower the axle with the jack.

INSTALLATIONHave the springs supporting the weight of the

vehicle when the arms and track bar fastenersare being torqued. If the springs are not at


their normal ride position, vehicle ride comfortand handling could be affected.

(1) Raise the axle with a floor jack and align coilsprings.

(2) Position the upper and lower suspension armson the axle brackets. Install nuts and bolts, DO NOTTORQUE BOLTS AT THIS TIME.

(3) Install track bar and attachment bolts, DONOT TORQUE BOLTS AT THIS TIME.

(4) Install shock absorber and tighten nuts to 60Nzm (44 ft. lbs.) torque

(5) Install stabilizer bar link and tighten nuts to36 Nzm (27 ft. lbs.) torque

(6) Install brake components refer to Group 5Brakes.

(7) Install axle vent hose(8) Align propeller shaft and pinion yoke reference

marks. Install U-joint straps and bolts tighten to 19Nzm (14 ft. lbs.) torque

(9) Install the wheels and tires.(8) Check and add gear lubricant if needed.(9) Remove support and lower the vehicle.(10) Tighten lower suspension arms bolts to 177

Nzm (130 ft. lbs.) torque.(11) Tighten upper suspension arms bolts to 75

Nzm (55 ft. lbs.) torque.(12) Tighten track bar bolts to 100 Nzm (74 ft. lbs.)

torque.

LUBRICANT CHANGEThe gear lubricant will drain quicker if the vehicle

has been recently driven.(1) Raise and support the vehicle.(2) Remove the lubricant fill hole plug from the dif-

ferential housing cover.(3) Remove the differential housing cover and

drain the lubricant from the housing.(4) Clean the housing cavity with a flushing oil,

light engine oil or lint free cloth. Do not use water,steam, kerosene or gasoline for cleaning.

(5) Remove the sealant from the housing and coversurfaces. Use solvent to clean the mating surfaces.

(6) Apply a bead of MOPARt Silicone Rubber Seal-ant to the housing cover (Fig. 1). Allow the sealantto cure for a few minutes.

Install the housing cover within 5 minutes af-ter applying the sealant. If not installed thesealant must be removed and another bead ap-plied.

(7) Install the cover and any identification tag.Tighten the cover bolts in a criss-cross pattern to 41Nzm (30 ft. lbs.) torque.

(8) Refill the differential with MOPARt HypoidGear Lubricant to bottom of fill plug hole.

Trac-Lok (limited slip) Differentials; A con-tainer of Trac-Lok Lubricant (friction modifier)should be added after repair service or a lubricantchange.

(9) Install the fill hole plug and lower the vehicle.LIMITED SLIP DIFFERENTIAL vehicles should

be road tested by making 10 to 12 slow figure eightturns. This maneuver will pump the lubricantthrough the clutch discs to eliminate a possible chat-ter noise complaint.

PINION SHAFT SEAL REPLACEMENT

REMOVAL(1) Raise and support the vehicle.(2) Remove wheel and tire assemblies(3) Mark the drive shaft yoke and pinion yoke for

installation alignment reference.(4) Remove the drive shaft from the yoke.(5) Rotate the pinion gear three or four times.

Make sure brakes are not dragging during thisprocedure.

(6) Measure the amount of torque (in Newtonmeters or inch pounds) necessary to rotate the piniongear with a torque wrench. Note the torque for in-stallation reference. It must be known to properlyadjust the pinion gear bearing preload torqueafter seal installation.

(7) Remove the pinion yoke nut and washer. UseRemover C-452 and Wrench C-3281 to remove thepinion yoke (Fig. 2).

(8) Mark the positions of the yoke and pinion gearfor installation alignment reference.

Fig. 1 Typical Housing Cover With Sealant


(9) Use Remover 7794A and slide hammer to re-move the pinion gear seal (Fig. 3).

INSTALLATION(1) Apply a light coating of gear lubricant on the

lip of pinion seal. Install seal with Installer D-163and Handle C-4171 (Fig. 4).

(2) Align the installation reference marks and in-stall yoke on the pinion gear with Installer W-162D.

(3) Install a new nut on the pinion gear. Tightenthe nut only enough to remove the shaft endplay.

CAUTION: Exercise care during bearing preloadtorque adjustment. Do not overtighten, or loosenand then re-tighten the nut. Do not exceed the bear-ing preload torque. The collapsible preload spaceron the pinion shaft will have to be replaced. Thebearing preload torque will be re-adjusted after-ward.

(4) Install a socket and inch pound torque wrenchon the pinion nut.

(5) Rotate the shaft with the torque wrench andnote the torque.

The required preload is equal to the amountat removal plus 0.56 Nzm (5 in. lbs.).

(6) Use Flange Wrench C-3281 to retain the yokeand shaft (Fig. 5). Tighten the shaft nut in verysmall increments.

(7) Continue tightening the shaft nut in small in-crements until the correct bearing preload torque isattained.

Fig. 2 Pinion Yoke Removal

Fig. 3 Seal Removal

Fig. 4 Pinion Seal Installation

Fig. 5 Tightening Pinion Shaft Nut


(8) Align the installation reference marks and at-tach the drive shaft to the yoke.

(9) Add API grade GL 5 hypoid gear lubricant tothe differential housing, if necessary.

(10) Install wheel and tire assemblies(11) Lower the vehicle.

AXLE SHAFT

REMOVAL(1) Raise and support the vehicle.(2) Remove the wheel and tire.(3) Remove the brake drum. If equipped with rear

disc brakes refer to Group 5 Brakes for procedure.(4) Clean all the foreign material from housing

cover area.(5) Loosen the housing cover bolts. Drain the lubri-

cant from the housing and the axle shaft tubes. Re-move the housing cover.

(6) Rotate the differential case so that the pinionmate gear shaft lock screw is accessible. Remove thelock screw and the pinion mate gear shaft from thecase (Fig. 6).

(7) Force the axle shaft in toward the center of thevehicle. Remove the axle shaft C-clip lock from theaxle shaft (Fig. 7).

(8) Remove the axle shaft. Use care to preventdamage to the axle shaft bearing and seal, which willremain in the axle shaft tube.

(9) Inspect the roller bearing contact surface onthe axle shaft for signs of brinelling, spalling and pit-ting.

(10) If any of these conditions exist, the axle shaftand bearing must be replaced.

INSTALLATION(1) Lubricate the bearing bore and seal lip with

gear lubricant. Insert the axle shaft through the seal,bearing, and engage it with the side gear splines.

Use care to prevent the shaft splines from dam-aging the axle shaft seal lip.

(2) Insert the C-clip lock in the end of the axleshaft. Push the axle shaft outward to seat the C-cliplock in the side gear.

(3) Insert the mate shaft into the case and throughthe thrust washers and pinion gears. Align the holein shaft with the hole in the differential case and in-stall the lock screw with Loctitet on the threads.Tighten the screw to 19 Nzm (14 ft. lbs.) torque.

(4) Install the cover and add fluid. Refer to theDrain and Refill in this section.

AXLE SHAFT SEAL AND BEARING

REMOVAL(1) Remove the axle shaft. Refer to the Removal

procedures in this Section.(2) Remove the axle shaft seal from the end of the

axle shaft tube with a small pry bar.(3) Remove the bearing if it appears damaged.The seal and bearing can be removed at the same

time with the bearing removal tool.(4) Remove the axle shaft bearing from the tube

(Fig. 8) with Bearing Removal Tool Set 6310 (T.Ar960-02).

(5) Inspect the axle shaft tube bore for roughnessand burrs. Remove as necessary.

CAUTION: Inspect the housing bore for burrs andremove if they exist.

INSTALLATIONDo not install the original axle shaft seal. Al-

ways install a new seal.(1) Wipe the bore in the axle shaft tube clean.(2) Install axle shaft bearing with Installer 6436

and Handle C-4171. Ensure part number on thebearing must go against the Installer.

Fig. 6 Mate Shaft Lock Screw

Fig. 7 Axle Shaft C-Clip Lock


(3) Install the new axle shaft seal (Fig. 9) with In-staller 6437 and Handle C-4171.

(4) Install the Axle Shaft. Refer to the installationprocedure.

DIFFERENTIAL REMOVALTo service the differential the axle shafts must be

removed. Refer to the removal procedures in thisGroup.

(1) Note the installation reference lettersstamped on the bearing caps and housing ma-chined sealing surface (Fig. 10).

(2) Remove the differential bearing caps.(3) Position Spreader W-129B with the tool dowel

pins seated in the locating holes (Fig. 11). Install theholddown clamps and tighten the tool turnbuckle fin-ger-tight.

(4) Install a pilot stud at the left side of the differ-

ential housing. Attach Dial Indicator to housing pilotstud. Load the indicator plunger against the oppositeside of the housing (Fig. 11) and zero the indicator.

CAUTION: Do not spread over 0.38 mm (0.015 in). Ifthe housing is over-separated, it could be distortedor damaged.

(5) Separate the housing enough to remove thecase from the housing. Measure the distance with thedial indicator (Fig. 11).

(6) Remove the dial indicator.(7) Pry the differential case loose from the housing.

To prevent damage, pivot on housing with the end ofthe pry bar against spreader (Fig. 12).

(8) Remove the case from housing. Mark or tagbearing cups and outboard shim/spacer (selectedthickness) indicating which side they were removed.Remove spreader from housing.

DIFFERENTIAL DISASSEMBLY(1) Remove the bearings from the differential case with

Press C-293PA, Plug SP3289, Adapter C-293-18 (Fig. 13).

Fig. 8 Axle Shaft Bearing Removal Tool

Fig. 9 Axle Shaft Seal Installation

Fig. 10 Bearing Cap Identification

Fig. 11 Spread Differential Housing


Place adapter rings so they do not damagethe bearing cage.

(2) Clamp the differential case in a vise equippedwith soft jaws. Remove and discard the ring gearbolts. Tap the ring gear with a rawhide or plasticmallet and remove (Fig. 14).

(3) Rotate the differential side gears and removethe pinion mate gears and thrust washers (Fig. 15).

(4) Remove the differential side gears and thrustwashers.

(5) Remove the case from the vise.

PINION REMOVAL/DISASSEMBLY(1) Remove the pinion yoke nut and washer. Use

Remover C-452 and Wrench C-3281 to remove thepinion yoke (Fig. 16).

(2) Remove the pinion gear from housing (Fig. 17).Catch the pinion with your hand to prevent it fromfalling and being damaged.

(3) Remove the pinion gear seal with a slide ham-mer or pry out with bar.

Fig. 12 Differential Removal

Fig. 13 Differential Bearing Removal

Fig. 14 Ring Gear Removal

Fig. 15 Pinion Mate Gear Removal


(4) Remove front bearing, and oil slinger ifequipped.

(5) Remove the front pinion bearing cup with Re-mover D-147 and Handle C-4171 (Fig. 18).

(6) Remove the rear bearing cup from housing (Fig.19). Use Remover D-148 and Handle C-4171.

(7) Remove the collapsible preload spacer (Fig. 20).(8) Remove the inner bearing from the pinion with

Puller C-293PA and Adapter C-293-39 (Fig. 21).Place adapter rings so they do not damage

the bearing cage.(9) Remove the depth shims from the pinion gear

shaft. Record the thickness of the depth shims.

CLEANING/INSPECTIONWash differential components with cleaning solvent

and dry with compressed air. Do not steam cleanthe differential components.

Wash bearings with solvent and towel dry. DONOT spin bearings with compressed air. Cup andbearing must be replaced as a matched setsonly.

Clean the axle shaft tubes and oil channel in hous-ing with a stiff wire and clean cloth.

Inspect for;

Fig. 16 Pinion Yoke Removal

Fig. 17 Remove Pinion Gear

Fig. 18 Front Bearing Cup Removal

Fig. 19 Rear Bearing Cup Removal


• Smooth appearance with no broken/dented sur-faces on the bearing rollers or the roller contact sur-faces.• Bearing cups must not be distorted or cracked.• Machined surfaces should be smooth and withoutany raised edges.• Raised metal on shoulders of cup bores should beremoved with a hand stone.

• Wear and damage to pinion gear mate shaft, pin-ion gears, side gears and thrust washers. Replace asa matched set only.• Ring and pinion gear for worn and chipped teeth.• Ring gear for damaged bolt threads. Replaced as amatched set only.• Pinion yoke for cracks, worn splines, pitted areas,and a rough/corroded seal contact surface. Repair orreplace as necessary.• Preload shims for damage and distortion. Installnew shims if necessary.

DIFFERENTIAL ASSEMBLY(1) Install the following components in the differ-

ential case.• Differential side gears and thrust washers• Pinion gears and thrust washers• Pinion gear mate shaft (align holes in shaft andcase)

(2) Lubricate all differential components with hy-poid gear lubricant.

PINION GEAR DEPTH INFORMATIONRing and pinion gears are supplied as matched sets

only. The identifying numbers for the ring and piniongear are etched into the face of each gear (Fig. 22). Aplus (+) number, minus (-) number or zero (0) isetched into the face of the pinion gear. This numberis the amount (in thousandths of an inch) the depthvaries from the standard depth setting of a pinionetched with a (0). The standard setting from the cen-terline of the ring gear to the back face of the pinionis 96.8 mm (3.813 inches) for Model 35 axles (Fig.23). The standard depth provides the best teeth con-tact pattern.

Fig. 20 Collapsible Preload Spacer

Fig. 21 Inner Bearing Removal

Fig. 22 Pinion Gear ID Numbers


THE BUTTON END ON THE PINION GEARHEAD IS NO LONGER A MACHINED-TO-SPECIFI-CATIONS SURFACE. DO NOT USE THIS SUR-FACE FOR PINION DEPTH SET-UP ORCHECKING (Fig. 23).

Compensation for pinion depth variance is achievedwith select shims. In production the shims are placedbetween the pinion gear and the inner pinion bearingcone. For service the shims are placed under the in-ner pinion bearing cup (Fig. 24).

If a new gear set is being installed, note thedepth variance etched into both pinion gears.Add or subtract the thickness of the originaldepth shims to compensate for the difference indepth variances. Refer to the Depth Variancecharts.

Note where Old and New Pinion Marking columnsintersect. Intersecting figure represents plus or mi-nus amount needed.

For example, if old pinion is plus (+) 1 and the newpinion is minus (-) 3, intersecting figure is (+) 0.004inch (0.10mm). Add this amount to the original shim.Or if the old pinion is (-) 3 and the new pinion is (-)2, intersecting figure is (-) 0.001 inch (0.025mm).Subtract this amount from original shim. Refer tothe Pinion Gear Depth Variance Chart.

Fig. 24 Shim Locations

PINION GEAR DEPTH VARIANCE

Fig. 23 Pinion Gear Head


PINION MEASUREMENT AND ASSEMBLY

PINION GEAR DEPTH MEASUREMENTPinion gear depth measurement is necessary

when;• Axle housing or differential case is replaced• Pinion select shim pack is unknown• Ring and pinion gears are replaced

Compensation for pinion depth variance is achievedwith select shims. In production the shims are placedbetween the pinion gear and the inner pinion bearingcone. For service the shims are placed under the in-ner pinion bearing cup.

Measurements are taken with pinion cups and pin-ion bearings installed in housing. Take measure-ments with Pinion Gauge Set 6774, Pinion Block6735 and Dial Indicator C-3339 (Fig. 25).

(1) Assemble Pinion Gauge Set, Pinion Block andpinion bearings. Install assembly into differentialpinion gear bore and hand tighten cone (Fig. 26).

(2) Place Arbor Disc 6732 on Arbor D-115-3 and po-sition in the bearing cradles (Fig. 27). Install differ-ential bearing caps on Arbor Discs and tighten capssnug only.

Arbor Discs have different steps to fit otheraxle sizes. Pick correct size step for axle beingserviced.

(3) Firmly place Scooter Block and Dial Indicatoron pinion height block tool and zero the dial indicatorpointer.

(4) Slide the Scooter Block across the arbor whileobserving indicator (Fig. 28). Record the longesttravel distance, whether inward (-) or outward (+),indicated by the pointer.

The plunger travel distance indicated, plus orminus the variance etched in the gear is the re-quired thickness for the depth shims.

(5) Measure the thickness of each depth shim witha micrometer and combine the shims necessary for

Fig. 25 Pinion Gear Depth Gauge Tools

Fig. 26 Pinion Height Block

Fig. 27 Gauge Tools In Housing

Fig. 28 Pinion Gear Depth Measurement


total required shim pack thickness. Include oilslinger or baffle thickness with the total shimpack thickness.

(6) Remove the measurement tools from the differ-ential housing.

PINION GEAR ASSEMBLY/INSTALLATION(1) Place the depth shims (and baffle if equipped)

in the pinion gear rear bearing bore. Install the bear-ing cup with Installer D-146 and Driver HandleC-4171 (Fig. 29). Ensure cup is correctly seated.

(2) Install the pinion front bearing cup with In-staller D-130 and Handle C-4171 (Fig. 30).

(3) Install pinion front bearing, oil slinger. Apply alight coating of gear lubricant on the lip of pinionseal. Install seal with Installer D-163 and HandleC-4171 (Fig. 31).

(4) Install the rear bearing (and slinger if used) onthe pinion gear with Installer W-262 (Fig. 32).

Fig. 29 Pinion Rear Bearing Cup Installation

Fig. 30 Pinion Front Bearing Cup Installation

Fig. 31 Pinion Seal Installation

Fig. 32 Rear Pinion Bearing Installation


(5) Install a new collapsible preload spacer on pin-ion shaft (Fig. 33).

(6) Install pinion gear into differential housing.(7) Install yoke with Installer W-162D and Wrench

C-3281 (Fig. 34).

(8) Install the yoke washer and a new nut on thepinion gear. Tighten nut to 271 Nzm (200 ft lbs.)min. Do not over-tighten.

CAUTION: Never loosen pinion gear nut to decreasepinion gear bearing preload torque and never exceedspecified preload torque. If preload torque is exceededa new collapsible spacer must be installed. The torquesequence will have to be repeated.

(9) Use Flange Wrench C-3281 to retain the yoke(Fig. 35). Slowly tighten the nut in small incrementsuntil the rotating torque is achieved. Measure thepreload torque frequently to avoid over-tight-ening the nut. The maximum pinion nut torqueis 475 Nzm (350 ft. lbs.).

(10) Check bearing preload torque with an inchpound torque wrench (Fig. 36). The torque necessaryto rotate the pinion gear should be;• Original Bearings — 1 to 3 Nzm (10 to 20 in. lbs.)• New Bearings — 1.7 to 3.9 Nzm (15 to 35 in. lbs.)

DIFFERENTIAL MEASUREMENT ANDINSTALLATION

DIFFERENTIAL SHIM PACK MEASUREMENT(1) Install the bearings on the hub with Installer

C-3716A and Driver Handle C-4171.(2) Match each bearing cup with bearing (original).

Install the cups on the bearings.(3) Install the differential case in the housing.(4) Install the outboard shim/spacer (selected thick-

ness) on each side between bearing cup and housing(Fig. 37). Use 0.142 in. (3.6 mm) as a starting point,shim/spacers are available in various thicknesses.

(5) Install the marked bearing caps in their correctpositions. Install and snug the bolts.

Fig. 33 Collapsible Preload Spacer

Fig. 34 Pinion Yoke Installation

Fig. 35 Tightening Pinion Nut


(6) Attach a dial indicator to the housing. Positionthe indicator plunger so that it contacts the ring gearmating surface (Fig. 38).

(7) Pry the differential case to one side and zerothe dial indicator pointer.

(8) Pry the differential case to the opposite sideand record indicator reading. Reading is additionalshim thickness needed for zero end play. For exam-ple, if reading was 0.008 inch (0.20 mm), an addi-tional 0.004 inch (0.10 - mm) thick shim will beneeded at each side zero end play.

(9) Install zero end-play shims on each side of case.

The differential bearings must be preloaded tocompensate for heat and load during operation.

(10) Add an additional 0.004 - inch (0.1 - mm) toeach outboard shim/spacer for bearing preload.

RING GEAR INSTALLATION(1) Invert the differential case and start two ring

gear bolts. This will provide case-to-ring gear bolthole alignment.

(2) Install new ring gear bolts and alternatelytighten to 95-122 Nzm (70-90 ft. lbs.) torque (Fig. 39).

Fig. 36 Check Pinion Gear Torque

Fig. 37 Differential Bearing Shim Installation

Fig. 38 Shim Measurement

Fig. 39 Ring Gear Bolt Installation


DIFFERENTIAL INSTALLATION(1) Position Spreader W-129B with the tool dowel

pins seated in the locating holes (Fig. 40). Install theholddown clamps and tighten the tool turnbuckle fin-ger-tight.

(2) Install a pilot stud at the left side of the differ-ential housing. Attach Dial Indicator to housing pilotstud. Load the indicator plunger against the oppositeside of the housing (Fig. 40) and zero the indicator.

CAUTION: Do not spread over 0.38 mm (0.015 in). Ifthe housing is over-separated, it could be distortedor damaged.

(3) Separate the housing enough to install the casein the housing. Measure the distance with the dialindicator (Fig. 40).

(4) Remove the dial indicator.(5) Install differential and outboard shim/spacer

(selected thickness) in housing.(6) Install case in the housing. Tap the differential

case to ensure the bearings are fully seated (Fig. 41).Remove the spreader.

(7) Install the bearing caps at their original loca-tions (Fig. 42). Tighten the bearing cap bolts to 77Nzm (57 ft. lbs.) torque.

BACKLASH AND CONTACT PATTERN ANALYSIS(1) Rotate assembly several revolutions to seat

bearings. Measure backlash at three equally spacedlocations around the perimeter of the ring gear witha dial indicator (Fig. 43).

The ring gear backlash must be within 0.12 -0.20 mm (0.005 - 0.008 inch). It cannot varymore than 0.05 mm (0.002 inch) between thepoints checked.

If backlash must be adjusted, spacers are availablein various thicknesses. Adjust the backlash accord-ingly (Fig. 44). DO NOT INCREASE THE TOTAL

SHIM PACK THICKNESS, EXCESSIVE BEAR-ING PRELOAD AND DAMAGE WILL OCCUR.

The ring gear teeth contact patterns will show ifthe pinion gear depth shim(s) have the correct thick-ness. It will also show if the ring gear backlash hasbeen adjusted correctly. The backlash must be main-tained within the specified limits until the correcttooth contact patterns are obtained.

(2) Apply a thin coat of hydrated ferric oxide, tothe ring gear teeth.

(3) Rotate the ring gear one complete revolution inboth directions while a load is being applied. Insert apry bar between the differential housing and the caseflange. This action will produce distinct contact pat-terns on both the drive side and coast side of the ringgear teeth.

Fig. 40 Spread Differential Housing Fig. 41 Differential Installation

Fig. 42 Differential Bearing Cap Reference Letters


(4) Note patterns in compound. Refer to (Fig. 45)for interpretation of contact patterns and adjust ac-cordingly.

Fig. 44 Backlash Shim Adjustment

Fig. 43 Ring Gear Backlash Measurement


Fig. 45 Gear Tooth Contact Patterns


FINAL ASSEMBLY(1) Install the axle shafts. Refer to Axle Shaft In-

stallation within this group.(2) Scrape the residual sealant from the housing

and cover mating surfaces. Clean the mating surfaceswith mineral spirits. Apply a bead of MOPARt Sili-cone Rubber Sealant on the housing cover (Fig. 46).Allow the sealant to cure for a few minutes.

Install the housing cover within 5 minutes af-ter applying the sealant. If not installed thesealant must be removed and another bead ap-plied.

(3) Install the cover on the differential with the at-taching bolts. Install the identification tag. Tightenthe cover bolts to 41 Nzm (30 ft. lbs.) torque.

CAUTION: Overfilling the differential can result inthe lubricant foaming and overheating.

(4) Refill the differential housing with the specifiedquantity of MOPARt Hypoid Gear Lubricant.

(5) Install the fill hole plug if used and tighten to34 Nzm (25 ft. lbs.) torque. Axles with rubber plugwill snap into place.

Fig. 46 Typical Housing Cover With Sealant


TRAC-LOK DIFFERENTIAL

OPERATIONIn a conventional differential, the torque applied to

the ring gear is transmitted to the axle shaftsthrough the differential gears. During normal opera-tion, the torque transmitted to each wheel is equal atall times. However, if one wheel spins, the oppositewheel will generate only as much torque as the spin-ning wheel.

In the Trac-Lok differential, part of the ring geartorque is transmitted through clutch packs. Theclutch packs contain multiple disc. The clutch willhave radial grooves on the plates, and concentricgrooves on the discs or bonded fiber material that issmooth appearance.

In operation, the Trac-Lok clutches are engaged bytwo concurrent forces. The first being preload forceexerted through Belleville spring washers containedin the clutch packs. The second from separatingforces generated by the side gears as torque is ap-plied through the ring gear (Fig. 1).

The Trac-Lok design provides differential actionneeded for turning corners and for driving straightahead. However, when one wheel looses traction, theclutch packs transfer additional torque to the wheelhaving the most traction. Trac-Lok differentials resistwheel spin on bumpy roads and provide more pullingpower when one wheel looses traction. Pulling poweris provided continuously until both wheels loose trac-tion. If both wheels slip due to unequal traction,Trac-Lok operation is normal. In extreme cases of dif-ferences of traction, the wheel with the least tractionmay spin.

NOISE DIAGNOSISIf a noise occurs when turning corners, the most

probable cause is incorrect or contaminated lubri-cant. Before removing the Trac-Lok unit for repair,drain, flush and refill the axle with the specified lu-bricant. Refer to Lubricant change in this Group.

A container of Trac-Lok Lubricant (friction modi-fier) should be added after repair service or a lubri-cant change.

Vehicles with a limited slip differential should beroad tested by making 10 to 12 slow figure eightturns. This maneuver will pump the lubricantthrough the clutch discs to eliminate a possible chat-ter or pop noise complaint.

Refer to Group 0, Lubrication and Maintenance foradditional information.

DIFFERENTIAL TEST

WARNING: WHEN SERVICING VEHICLES WITH ALIMITED SLIP DIFFERENTIAL DO NOT USE THE EN-GINE TO TURN THE AXLE AND WHEELS. BOTH

REAR WHEELS MUST BE RAISED AND THE VEHI-CLE SUPPORTED. A LIMITED SLIP AXLE CAN EX-ERT ENOUGH FORCE (IF ONE WHEEL IS INCONTACT WITH THE SURFACE) TO CAUSE THEVEHICLE TO MOVE.

The differential can be tested without removing thedifferential case by measuring rotating torque. Makesure brakes are not dragging during this measure-ment.

(1) Engine of, transmission in neutral, and parkingbrake off.

(2) Place blocks in front and rear of both frontwheels.

(3) Jack up one rear wheel until it is completely offthe ground.

(4) Remove wheel and bolt Special Tool 6790 tostuds.

(5) Use torque wrench on special tool to rotatewheel and read rotating torque (Fig. 2).

(6) If rotating torque is less than 22 Nzm (30 ft.lbs.) or more than 271 Nzm (200 ft. lbs.) on eitherwheel the unit should be service.

Fig. 1 Limited Slip Differential Operation—BothWheels Driving


DIFFERENTIAL OVERHAULThe Trac-Lok (limited-slip) differential components

are illustrated in (Fig. 3). Refer to this illustrationduring repair service.

DISASSEMBLYService to the Trac-Lok differential requires the use

of Tool Set C-4487 (J-23781). Refer to Model 35 Axlesection in this Group for Differential Removal andInstallation.

(1) Clamp one axle shaft in a vise equipped withsoft jaws (Fig. 4).

Fig. 3 Trac-Lok Differential Components

Fig. 2 Trac-Loc Test

Fig. 4 Axle Shaft As Holding Fixture


(2) Position the differential case on the axle shaft(Fig. 5). Place shop towels under the differential toavoid damage during removal of the ring gear (Fig.5).

(3) Remove and discard the ring gear bolts. Tapthe ring gear with a rawhide or plastic mallet and re-move (Fig. 6).

(3) Remove the pinion gear mate shaft lock screw(Fig. 7).

(5) Remove the pinion gear mate shaft with a driftand hammer (Fig. 8).

(6) Install and lubricate Step Plate C-4487-1 (Fig.9).

(7) Assemble Threaded Adapter C-4487-3 into topside gear. Thread forcing Screw C-4487-2 intoadapter until it becomes centered in adapter plate.

Fig. 5 Differential Case On Shaft

Fig. 6 Ring Gear Removal

Fig. 7 Mate Shaft Lock Screw

Fig. 8 Mate Shaft Removal

Fig. 9 Step Plate Tool Installation


(8) Position a small screw driver in slot ofThreaded Adapter C-4487-3 (Fig. 10) to preventadapter from turning.

(9) Tighten forcing screw tool enough to relieveclutch pack tension. Remove both pinion thrustwashers (Fig. 11).

(10) Loosen the forcing screw tool until the clutchpack tension is relieved.

(11) Insert Turning Bar C-4487-4 in case. Rotatecase with tool until pinion gears can be removed (Fig.12).

(12) Remove top side gear and clutch pack. Keepplates in correct order during removal (Fig. 13).

(13) Remove case from fixture. Remove remainingclutch pack.

(14) Remove clutch pack retaining clips. Mark eachclutch pack for installation reference.

CLEANING AND INSPECTION(1) Clean all components in cleaning solvent. Dry

components with compressed air.

Fig. 10 Threaded Adapter Installation

Fig. 11 Remove Pinion Thrust Washer

Fig. 12 Pinion Gear Removal

Fig. 13 Side Gear & Clutch Disc Removal


(2) Inspect clutch pack plates for wear, scoring ordamage. Replace both clutch packs if any one compo-nent in either pack is damaged.

(3) Inspect side and pinion gears. Replace any gearthat is worn, cracked, chipped or damaged.

(4) Inspect differential case and pinion shaft. Re-place if worn or damaged.

PRESOAK PLATES AND DISCPlates and dics with fiber coating (no groves or

lines) must be presoaked in Friction Modifier beforeassembly. Soak plates and discs for a minimum of 20minutes. Add remaining Friction Modifier to differen-tial after assembly.

ASSEMBLYThe clutch discs are replaceable as complete sets

only. If one clutch disc pack is damaged, bothpacks must be replaced.

Lubricate each component with gear lubricant be-fore assembly.

(1) Assemble the clutch discs into packs secure discpacks with retaining clips (Fig. 14).

(2) Position assembled clutch disc packs on theside gear hubs.

(3) Position case on axle fixture.(4) Install clutch pack and side gear in lower bore

(Fig. 15). Be sure clutch pack retaining clips re-main in position and are seated in the casepockets.

(5) Install lubricated Step Plate C-4487-1 on firstclutch pack (Fig. 16).

(6) Install the upper side gear and clutch disc pack(Fig. 16).

(7) Hold assembly in position. Insert Threaded

Adapter C-4487-3 into top side gear, insert forcingScrew C-4487-2.

(8) Tighten forcing screw tool to compress clutchdiscs.

(9) Install pinion gears. Rotate case with TurningBar C-4487-4. Make sure holes of pinion mate gearsare aligned with case.

(10) Tighten forcing screw to compress theBelleville plates. Lubricate and install pinion gearthrust washers with a small screw driver.

(11) Remove forcing screw, threaded adapter andstep plate. Install pinion gear mate shaft, align holesin shaft and case.

(12) Install the pinion mate shaft lock screw fingertight to hold shaft durning installation.

Fig. 14 Clutch Disc Pack

Fig. 15 Clutch Discs & Lower Side Gear Installation

Fig. 16 Upper Side Gear & Clutch Disc PackInstallation


If replacement gears and thrust washers wereinstalled, it is not necessary to measure thegear backlash. Correct fit is due to close ma-chining tolerances during manufacture.

(13) Invert the differential case and start two ringgear bolts. This will provide case-to-ring gear bolthole alignment.

(14) Install new ring gear bolts and alternatelytighten to 95-122 Nzm (70-90 ft. lbs.) torque (Fig. 17).

(15) Lubricate all differential components with hy-poid gear lubricant.

AXLE SPECIFICATIONS

MODEL 35 AXLEAxle Type ...............................Semi-Floating HypoidLubricant................Thermally Stable SAE 80W-90Lubricant Trailer Tow.............Synthetic 75W-140Lube Capacity ................................1.66 L (3.5 pts.)Axle Ratio....................................................3.55 3.73Diff. Brg. Preload......................0.1 mm (0.004 in.)Side Gear Clearance..............0-0.15 mm (0-0.006)

Ring GearDiameter .......................................19.2 cm (7.562 in.)Backlash....................0.12-0.20 mm (0.005-0.008 in.)Pinion Std. Depth ...................96.8 mm (3.813 in.)Pinion Bearing PreloadOriginal Bearing ..................1-2 Nzm (10-20 in. lbs.)New Bearing......................1.5-4 Nzm (15-35 in. lbs.)

TORQUE SPECIFICATIONS

REAR SUSPENSION COMPONENTS

DESCRIPTION................................................TORQUEShock Upper Nut .....................70 Nzm (52 ft. lbs.)Shock Lower Nut .....................92 Nzm (68 ft. lbs.)Suspension Arm UpperNuts ..............................................75 Nzm (55 ft. lbs.)Suspension Arm LowerNuts ..........................................177 Nzm (130 ft. lbs.)Stabilizer BarClamp Bolt...................................54 Nzm (40 ft. lbs.)Link Nut ......................................36 Nzm (27 ft. lbs.)

Track BarFrame Bracket Nut...................100 Nzm (74 ft. lbs.)Axle Bracket Bolt......................100 Nzm (74 ft. lbs.)

MODEL 35 AXLE

DESCRIPTION................................................TORQUEFill Hole Plug ...........................34 Nzm (25 ft. lbs.)Diff. Cover Bolt ........................41 Nzm (30 ft. lbs.)Bearing Cap Bolt .....................77 Nzm (57 ft. lbs.)Ring Gear Bolt .............95-122 Nzm (70-90 ft. lbs.)

Fig. 17 Ring Gear Bolt Installation


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