95ZJ_2.PDF

FRONT SUSPENSION AND AXLE

CONTENTS

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AXLE NOISE/VIBRATION DIAGNOSIS . . . . . . . . 12AXLE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . 40FRONT SUSPENSION . . . . . . . . . . . . . . . . . . . . . 8GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1

MODEL 30 AXLE AND TUBE AXLE (2WD) . . . . 16TORQUE SPECIFICATIONS . . . . . . . . . . . . . . . . 40WHEEL ALIGNMENT . . . . . . . . . . . . . . . . . . . . . . 4

GENERAL INFORMATION

FRONT SUSPENSIONThe Grand Cherokee front suspension is a link/coil

design comprised of (Fig. 1);• Drive axle (4WD), tube axle (2WD)• Track bar• Stabilizer bar• Upper and lower suspension arms• Coil springs• Dual-action shock absorbers• Jounce bumpers

The link/coil suspension allows each wheel to adaptto different road surfaces without greatly affectingthe opposite wheel. Wheels are attached to a hub/bearings which bolts to the knuckles. The hub/bear-ing is not serviceable and is replaced as a unit.Steering knuckles pivot on replaceable ball studs at-tached to the axle tube yokes.

The upper and lower suspension arms use bushingsto isolate road noise. The suspension arms are boltedto the frame and axle through the rubber bushings.

Fig. 1 Front Suspension

ZJ FRONT SUSPENSION AND AXLE 2 - 1

The lower suspension arm uses cam bolts at the axleto allow for caster and pinion angle adjustment. Thesuspension arm travel is limited through the use ofjounce bumpers in compression and shocks absorbersin rebound.

The coil springs control ride quality and maintainproper ride height. The coil springs mount up in thewheelhouse which is part of the unitized bodybracket. A rubber doughnut isolator is located be-tween the top of the spring and the body. The bottomof the spring seats on a axle pad and is retained witha clip.

The shock absorbers dampen jounce and reboundmotion of the vehicle over various road conditions.The top of the shock absorbers are bolted to the body.The bottom of the shocks are bolted to the axlebrackets.

The stabilizer bar is used to control vehicle bodyroll during turns. The spring steel bar helps to con-trol the vehicle body in relationship to the suspen-sion. The bar extends across the front underside ofthe chassis and connects to the frame rails. Links areconnected from the bar to the axle brackets. Stabi-lizer bar mounts are isolated by rubber bushings.

The track bar is used to control front axle lateralmovement. The bar is attached to a frame railbracket with a ball stud and isolated with a bushingat the axle bracket.

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.

FRONT DRIVE AXLEThe integral type housing, has the centerline of the

pinion set below the centerline of the ring gear.The axles are equipped with A.B.S. brake systems.

The A.B.S. tone rings are pressed onto the axle shaftnear the hub and knuckle. For additional informationon the A.B.S. system refer to Group 5, Brakes.

The Model 30 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.

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-

Fig. 2 Model 30 Differential Cover

Fig. 3 Differential Operation—Straight-Ahead Driving

2 - 2 FRONT SUSPENSION AND AXLE ZJ

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.

TUBE AXLE (2WD VEHICLES)The front axle used on two wheel drive vehicles is

a one-piece, tubular axle (Fig. 5). The tubular axle

mounts in the same bracketry as does the four wheeldrive front axle. The steering knuckles and hub bear-ing assemblies are the same as used on the Model 30drive axle.

Fig. 4 Differential Operation—On Turns

Fig. 5 Front Axle—2WD Vehicles


WHEEL ALIGNMENT

GENERAL INFORMATIONFour wheel alignment involves the correct position-

ing of the wheels in relation to the vehicle. The posi-tioning is accomplished through suspension andsteering linkage adjustments. An alignment is con-sidered essential for efficient steering, good direc-tional stability and to minimize tire wear. The mostimportant measurements of an alignment are caster,camber toe and thrust angle.

Routine inspection of the front suspensionand steering components is a good preventativemaintenance practice. Inspection also helps toensure safe operation of the vehicle.• CASTER is the forward or rearward tilt of thesteering knuckle from vertical. Tilting the top of theknuckle forward provides negative caster. Tilting thetop of the knuckle rearward provides positive caster.Positive caster promotes directional stability. Thisangle enables the front wheels to return to a straightahead position after turns (Fig. 1).• CAMBER is the inward or outward tilt of thewheel relative to the center of the vehicle. Tilting thetop of the wheel inward provides negative camber.Tilting the top of the wheel outward provides positive

camber. Incorrect camber will cause wear on the in-side or outside edge of the tire (Fig. 1).• TOE is the difference between the leading insideedges and trailing inside edges of the front tires (Fig.1). Uneven wheel toe position cause’s unstable steer-ing, uneven tire wear and steering wheel off-center.The wheel toe position is the final front wheel align-ment adjustment.• THRUST ANGLE is the angle of the rear axle rel-ative to the vehicle center line. If this angle is off thevehicle may drift or wander.• STEERING AXIS INCLINATION ANGLE is mea-sured in degrees. It is the angle that the steeringknuckles are tilted (Fig. 1). The inclination angle hasa fixed relationship with the camber angle. It will notchange except when a spindle or ball stud is dam-aged or bent. The angle is not adjustable and thedamaged component(s) must be replaced to correctmis-alignment.

CAUTION: Do not attempt to modify any suspen-sion or steering component by heating and bend-ing.

Fig. 1 Wheel Alignment Angles


PRE-ALIGNMENT INSPECTIONBefore starting a front wheel alignment, the follow-

ing inspection and necessary corrections must becompleted.

(1) Tires with the same recommended air pressure,size, and tread wear. Refer to Group 22, Wheels andTires for diagnosis information.

(2) Front wheel bearings for wear.(3) Ball studs, steering linkage pivot points and

steering gear for looseness, roughness, binding orwear. Refer to Group 19, Steering for additional in-formation.

(4) Wheels for excessive radial, lateral runout andunbalance. Refer to Group 22, Wheels and Tires fordiagnosis information.

(5) Suspension components for wear and noise.Check components for correct torque. Refer to Groups2 and 3, Suspension and Axle for additional informa-tion.

ALIGNMENT MEASUREMENTS ANDADJUSTMENTS

Before each alignment reading the vehicle shouldbe jounced (rear first, then front). Grasp eachbumper at the center and jounce the vehicle up anddown three times. Always release the bumper in thedown position.

CAMBERThe wheel camber angle (Fig. 1) is preset. This an-

gle is not adjustable and cannot be altered.

CASTERCheck the caster of the front axle for correct angle

(fig. 1). Be sure the axle is not bent or twisted. Roadtest the vehicle and observe the steering wheel re-turn-to-center position. Low caster will cause poorsteering wheel returnability.

During the road test, turn the vehicle to both theleft and right. If the steering wheel returns to thecenter position unassisted, the caster angle is correct.However, if steering wheel does not return towardthe center position unassisted, a low caster angle isprobable.

Front aster can be adjusted by loosening and rotat-ing the cams on the lower suspension arm (Fig. 2).Changing caster angle will also change thefront propeller shaft angle. The propeller shaftangle has priority over caster. Refer to Group16, Propeller Shafts for additional information.

TOE POSITIONThe wheel toe position adjustment should be the fi-

nal adjustment.(1) Start the engine and turn wheels both ways be-

fore straightening the steering wheel. Center and se-cure the steering wheel.

(2) Loosen the adjustment sleeve clamp bolts (Fig.3).

Fig. 2 Cam Adjuster

Fig. 3 Steering Linkage


SUSPENSION AND STEERING SYSTEM DIAGNOSIS


(3) Adjust the right wheel toe position with thedrag link. Turn the sleeve until the right wheel is atthe correct positive TOE-IN position. Position theclamp bolts as shown (Fig. 4) and tighten to 49 Nzm(36 ft. lbs.) torque. Make sure the toe setting doesnot change during clamp tightening.

(4) Adjust the left wheel toe position with the tierod. Turn the sleeve until the left wheel is at the

same TOE-IN position as the right wheel. Positionthe clamp bolts as shown (Fig. 4) and tighten to 27Nzm (20 ft. lbs.) torque. Make sure the toe settingdoes not change during clamp tightening.

(5) Verify the right toe setting.

Fig. 4 Drag Link and Tie Rod Clamp Location

ALIGNMENT SPECIFICATIONS


FRONT SUSPENSION

INDEX

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Axle Bushing Replacement . . . . . . . . . . . . . . . . . . . 9Coil Spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Lower Suspension Arm . . . . . . . . . . . . . . . . . . . . . . 9Service Information . . . . . . . . . . . . . . . . . . . . . . . . . 8Shock Absorber . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Spring and Shock Diagnosis . . . . . . . . . . . . . . . . . 10Stabilizer Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Track Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Upper Suspension Arm . . . . . . . . . . . . . . . . . . . . . . 9

SERVICE INFORMATIONPeriodic lubrication of the front suspension (steer-

ing) system components is required. Refer to Group0, Lubrication And Maintenance for the recom-mended maintenance schedule.

CAUTION: Suspension components with rubberbushings should be tightened with the vehicle atnormal height. It is important to have the springssupporting the weight of the vehicle when the fas-teners are torqued. If springs are not at their normalride position, vehicle ride comfort could be affectedand premature bushing wear may occur. Rubberbushings must never be lubricated.

TRACK BAR

REMOVAL(1) Raise and support the vehicle.(2) Remove the cotter pin and nut from the ball

stud end at the frame rail bracket (Fig. 1).A puller tool may be necessary to separate the

ball stud from the frame rail bracket.(3) Remove the bolt and flag nut from the axle

shaft tube bracket (Fig. 1). Remove the track bar.

INSTALLATION(1) Install the track bar at axle tube bracket.

Loosely install the retaining bolt and flag nut (Fig.1).

(2) It may be necessary to pry the axle assemblyover to install the track bar at the frame rail. Installtrack bar at the frame rail bracket (Fig. 1). Installthe retaining nut on the stud.

(3) Remove the supports and lower the vehicle.(4) Tighten the bolt at the axle shaft tube bracket

to 75 Nzm (55 ft. lbs.) torque.(5) Tighten the ball stud nut to 81 Nzm (60 ft. lbs.)

torque. Install a new cotter pin.(6) Check alignment if a new track bar was in-

stalled.

STABILIZER BAR

REMOVAL(1) Raise and support the vehicle.(2) Disconnect the stabilizer bar links from the

axle brackets (Fig. 2).(3) Disconnect the stabilizer bar from the links.(4) Disconnect the stabilizer bar clamps from the

frame rails. Remove the 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.).

Fig. 1 Track Bar


(2) Install the links and grommets onto the stabi-lizer bar and axle brackets (Fig. 2). Tighten the nutat the connecting links at the axle bracket to 95 Nzm(70 ft. lbs.) torque.

(3) Tighten the stabilizer bar to connecting linknut to 36 Nzm (27 ft. lbs.) torque.

(4) Remove the supports and lower the vehicle.

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).(3) Remove the nut and bolt (Fig. 3) at the frame

rail 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).(3) Remove the supports and lower the vehicle.(4) Tighten the nut at the axle and frame bracket

to 75 Nzm (55 ft. lbs.) torque.

AXLE BUSHING REPLACEMENT(1) Remove the upper suspension arm from axle.

Refer to Upper Suspension Arm Removal in thisGroup.

(2) Insert Spacer 7932-3 (J-35581-3) around thebushing in the axle bracket ears (Fig. 4).

(3) Assemble and install Bushing Removal/In-staller (Fig. 4).

(4) Remove the bushing by tightening the hex-headon Long Nut.

For two-wheel drive axles and right side onModel 30 axle, do not remove Spacer 7932-3 (J-35581-3) at this time.

(5) Position the new bushing on Installer.(6) Install the bushing by tightening the hex-head

on Long Nut (Fig. 5). Remove Spacer 7932-3 (J-35581-3).

(7) Install the upper suspension arm to axle. Referto Upper Suspension Arm Installation in this Group.

LOWER SUSPENSION ARM

REMOVAL(1) Raise and support the vehicle.

Fig. 2 Stabilizer Bar

Fig. 3 Upper and Lower Suspension Arms

Fig. 4 Axle Bracket Bushing Removal


(2) Paint or scribe alignment marks on the cam ad-justers and suspension arm for installation reference(Fig. 6).

(3) Remove the lower suspension arm nut, camand cam bolt from the axle (Fig. 3).

(4) Remove the nut and bolt from the frame railbracket and remove the lower suspension arm (Fig.6).

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

bracket and frame rail bracket.(2) Install the rear bolts and finger tighten the

new nuts (Fig. 6).(3) Install a new cam bolt, cam and new nut in the

axle. Re-align the reference marks.(4) Install the bolts and finger tighten the new

nuts (Fig. 6).(5) Lower the vehicle.(6) Tighten the front and rear nuts to 115 Nzm (85

ft. lbs.) torque.(7) Check the alignment if new parts were in-

stalled.

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 stoppedby tightening the attaching nuts. If the squeak noisepersists, inspect for damaged and worn bushings,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) Remove the nut, retainer and grommet from

the upper stud in the engine compartment (Fig. 7).(2) Remove the lower nuts and bolts from the axle

bracket (Fig. 7). Remove the shock absorber.

INSTALLATION(1) Position the lower retainer and grommet on the

upper stud. Insert the shock absorber through theshock tower hole.

(2) Install the lower bolts and nuts. Tighten nutsto 28 Nzm (250 in. lbs.) torque.

(3) Install the upper grommet and retainer on thestud in the engine compartment. Install the nut andtighten to 23 Nzm (17 ft. lbs.) torque.

COIL SPRING

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

draulic jack under the axle to support it.(2) Paint or scribe alignment marks on the cam ad-

justers and axle bracket for installation reference(Fig. 6).

(3) Mark and disconnect the front propeller shaftfrom the axle.

Fig. 5 Axle Bracket Bushing Installation

Fig. 6 Cam Adjuster


(4) Remove the lower suspension arm nut, camand cam bolt from the axle (Fig. 3).

(5) Disconnect the stabilizer bar link and shock ab-sorber from the axle.

(6) Disconnect the track bar from the frame railbracket.

(7) Disconnect the drag link from the pitman arm.(8) Lower the axle until the spring is free from the

upper mount. Remove the coil spring retainer boltand remove the spring.

(9) Remove the jounce bumper if necessary fromthe upper spring mount (Fig. 7).

INSTALLATION(1) Install the jounce bumper on the upper spring

mount. Tighten the bolts to 42 Nzm (31 ft. lbs.)torque (Fig. 7).

(2) Position the coil spring on the axle pad. Installthe spring retainer and bolt.

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

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

(5) Install the lower suspension arm to the axle.(6) Install the front propeller shaft to the axle.(7) Install drag link to pit man arm.(8) Remove the supports and lower the vehicle.(9) Tighten all suspension components to proper

torque.Fig. 7 Coil Spring & Shock Absorber


AXLE NOISE/VIBRATION DIAGNOSIS

INDEX

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Driveline Snap . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Gear and Bearing Noise . . . . . . . . . . . . . . . . . . . . 12General Information . . . . . . . . . . . . . . . . . . . . . . . 12

Low Speed Knock . . . . . . . . . . . . . . . . . . . . . . . . . 13Vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

GENERAL INFORMATIONAxle bearing problem conditions are usually caused

by:• Insufficient or incorrect lubricant• Foreign matter/water contamination• Incorrect bearing preload torque adjustment• Incorrect backlash ( to tight)

When serviced, the bearings must be cleaned thor-oughly. They should be dried with lint free shop tow-els. Never dry 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• Overloading (excessive engine torque)• Exceeding vehicle weight capacity• 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. This will cause accel-erated wear and contribute to early failure. Mis-ad-justment will produce noise. If a mis-adjustmentcondition is not corrected, component failure can re-sult.

Excessive bearing preload may not be noisy. Thiscondition will cause high temperature which can re-sult in bearing failure.

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 speedknock.

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 shaftCheck for loose or damaged front end components

or 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.


SERVICE DIAGNOSIS


SERVICE DIAGNOSIS (CONT’D)


MODEL 30 AXLE AND TUBE AXLE (2WD)

INDEX

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Axle Bushing Replacement . . . . . . . . . . . . . . . . . . 26Axle Shaft Oil Seals . . . . . . . . . . . . . . . . . . . . . . . 26Axle Shaft— Cardan U-Joint . . . . . . . . . . . . . . . . . 20Axle Shaft— CV-Joint . . . . . . . . . . . . . . . . . . . . . . 21Backlash and Contact Pattern Analysis . . . . . . . . . 37Cleaning/Inspection . . . . . . . . . . . . . . . . . . . . . . . . 29Differential and Pinion Measurement . . . . . . . . . . . 32Differential Assembly . . . . . . . . . . . . . . . . . . . . . . . 30Differential Disassembly . . . . . . . . . . . . . . . . . . . . 26Differential Installation . . . . . . . . . . . . . . . . . . . . . . 36Differential Removal . . . . . . . . . . . . . . . . . . . . . . . 26Differential Shim Pack Measurement and

Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Drive Axle Assembly Replacement . . . . . . . . . . . . . 16Final Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . 40General Information . . . . . . . . . . . . . . . . . . . . . . . 16Hub Bearing and Axle Shaft . . . . . . . . . . . . . . . . . 19Lubricant Change . . . . . . . . . . . . . . . . . . . . . . . . . 17Lubricant Specifications . . . . . . . . . . . . . . . . . . . . . 16Pinion Gear Assembly/Installation . . . . . . . . . . . . . 33Pinion Gear Depth Information . . . . . . . . . . . . . . . 30Pinion Removal/Disassembly . . . . . . . . . . . . . . . . . 28Pinion Shaft Seal Replacement . . . . . . . . . . . . . . . 18Steering Knuckle and Ball Studs . . . . . . . . . . . . . . 24

GENERAL INFORMATIONThe housing for Model 30 front axles consists of an

iron center casting with tubes on each side. Thetubes are pressed into and welded to the differentialhousing.

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

The axle has a vent used to relieve internal pres-sure caused by lubricant vaporization and internalexpansion.

The axles are equipped with semi-floating axleshafts, meaning that loads are supported by the hubbearings. The axle shafts are retained by nuts at thehub bearings. The hub bearings are bolted to thesteering knuckle at the outboard end of the axle tubeyoke. The hub bearings are serviced as an assembly.

The axles are equipped with ABS brake sensors.The sensors are attached to the knuckle assembliesand tone rings are pressed on the axle shaft. Usecare when removing axle shafts as NOT to dam-age the tone wheel or the sensor.

The stamped steel cover provides a means for in-spection and servicing the differential.

The Model 30 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 a rollpin. Differential bearing preload and ring gear back-lash is adjusted by the use of shims. The shims arelocated between the differential bearing cones andcase. Pinion bearing preload is set and maintained bythe use of a collapsible spacer.

LUBRICANT SPECIFICATIONSMulti-purpose, hypoid gear lubricant should be

used for Model 30 axles. The lubricant should haveMIL-L-2105C and API GL 5 quality specifications.MOPARt Hypoid Gear Lubricant conforms to both ofthese specifications.• The factory fill for the Model 30 axle is SAE Ther-mally Stable 80W-90 gear lubricant• The factory installed lubricant quantity for theNON-DISCONNECT TYPE AXLE is 4061 fluid oz.

Refer to Group 0, Lubrication and Maintenance foradditional information.

CAUTION: If axle is submerged in water, lubricantmust be replaced immediately to avoid contamina-tion.

DRIVE AXLE ASSEMBLY REPLACEMENT

REMOVAL(1) Raise vehicle and position support stands un-

der the frame rails behind the lower suspension armbrackets.

(2) Remove the front wheels.(3) Remove the brake components and ABS brake

sensor (if equipped). Refer to Group 5—Brakes.(4) On 4WD vehicles, disconnect the axle vent

hose.(5) On 4WD vehicles, mark the drive shaft yoke

and axle pinion yoke for alignment reference. Discon-nect the drive shaft from the axle.

(6) Disconnect the stabilizer bar link at the axlebracket.

(7) Disconnect the shock absorbers from axlebracket.

(8) Disconnect the track bar from the axle bracket.


(9) Disconnect the tie rod and drag link from thesteering knuckle. Disconnect the steering dampenerfrom the axle bracket.

(10) Support the axle with a hydraulic jack underthe differential.

(11) Disconnect the upper and lower suspensionarms from the axle bracket.

(12) Lower the jack enough to remove the axle.The coil springs will drop with the axle.

(13) Remove the coil springs from the axle bracket.

INSTALLATION

CAUTION: Suspension components with rubberbushings should be tightened with the vehicle atnormal height. It is important to have the springssupporting the weight of the vehicle when the fas-teners are torqued. If springs are not at their normalride position, vehicle ride comfort could be affectedand premature bushing wear may occur. Rubberbushings must never be lubricated.

(1) Install the springs, retainer clip and bolts.(2) Support the axle on a hydraulic jack under the

differential. Position the axle under the vehicle.(3) Raise the axle with a floor jack and align it

with the spring pads.(4) Position the upper and lower suspension arm at

the axle bracket. Install bolts and nuts fingertighten.

(5) Connect the track bar to the axle bracket andinstall the bolt. Do not tighten at this time.

It is important that the springs support theweight of the vehicle when the track bar is con-nected. If the springs are not at their usual po-sition, the vehicle ride comfort could beaffected.

(6) Install the shock absorber and tighten nuts to27 Nzm (20 ft. lbs.) torque.

(7) Install the stabilizer bar link to the axlebracket. Tighten the nut to 95 Nzm (70 ft. lbs.)torque.

(8) Install the drag link and tie rod to the steeringknuckles and tighten the nuts to 47 Nzm (35 ft. lbs.)torque. Install the steering dampener to the axlebracket and tighten the nut to 75 Nzm (55 ft. lbs.)torque.

(9) Install the brake components and ABS brakesensor (if equipped). Refer to Group 5—Brakes.

(10) On 4WD vehicles, connect the vent hose to thetube fitting.

(11) On 4WD vehicles, align the reference marksand connect the drive shaft to the axle yoke. Tightenthe U-joint clamp bolts to 19 Nzm (14 ft. lbs.) torque.

(12) Check differential lubricant and add if neces-sary.

(13) Install the wheel and tire.(14) Remove the supports and lower the vehicle.

(15) Tighten the upper suspension arm nuts to 75Nzm (55 ft. lbs.) torque. Tighten the lower suspensionarm nuts to 115 Nzm (85 ft. lbs.) torque.

(16) Tighten the track bar bolt at the axle bracketto 75 Nzm (55 ft. lbs.) torque.

(17) Check the front wheel alignment.

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 and oil channels with

a flushing oil, light engine oil or lint free cloth. Donot use water, steam, kerosene or gasoline forcleaning.

(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 the bottom of fill plug hole.

(9) Install the fill hole plug and lower the vehicle.

Fig. 1 Typical Housing Cover With Sealant


PINION SHAFT SEAL REPLACEMENT

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

for installation alignment reference.(4) Remove the propeller 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 Newton-meters 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.

(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 the bearing preloadtorque adjustment. Do not over-tighten, or loosenand then re-tighten the nut. Do not exceed the bear-ing preload torque. The collapsible preload spacer

on 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 amount re-corded during removal plus 0.56 Nzm (5 in. lbs.).The used bearing preload torque must neverexceed 2.25 Nzm (20 in. lbs.)

(6) Use Flange Wrench C-3281 to retain the yokeand shaft (Fig. 5). Tighten the shaft nut in verysmall increments. Vehicles with Type 3 propellershaft use Flange Wrench C-3281 with 2 bolts in-stalled into the flange (Fig. 6).

Fig. 2 Pinion Yoke Removal

Fig. 3 Seal Removal

Fig. 4 Pinion Seal Installation


(7) Continue tightening the shaft nut in small in-crements until the correct bearing preload torque isattained. Tighten the pinion shaft nut:• No less than 217 Nzm (160 ft. lbs.) torque• No greater than 352 Nzm (260 ft. lbs.) torque

(8) Align the installation reference marks and at-tach the propeller 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.

HUB BEARING AND AXLE SHAFT

REMOVAL(1) Raise and support the vehicle.(2) Remove the wheel and tire assembly.(3) Remove the brake components from the axle,

refer to Group 5, Brakes.(4) Remove the cotter pin, nut retainer and axle

hub nut (Fig. 7).(5) Remove the hub to knuckle bolts (Fig. 7). Re-

move the hub from the steering knuckle and axleshaft.

(6) Remove the disc brake rotor shield from thebearing carrier (Fig. 7).

(7) On 4WD vehicles, remove the axle shaftfrom the housing. Avoid damaging the axleshaft oil seals in the differential.

Fig. 6 Tightening Pinion Nut with Type 3 Shaft

Fig. 7 Hub, Knuckle and Axle Shaft

Fig. 5 Tightening Pinion Nut


INSTALLATION(1) Thoroughly clean the axle shaft and apply a

thin film of Mopar Wheel Bearing Grease to the shaftsplines, seal contact surface, hub bore.

(2) On 4WD vehicles, install the axle shaft into thehousing and differential side gears. Avoid damagingthe axle shaft oil seals in the differential.

(3) Install the hub bearing and brake dust shieldto the knuckle.

(4) Install the hub to knuckle bolts and tighten to102 Nzm (75 ft. lbs.) torque.

(5) Install the hub washer and nut. Tighten thehub nut to 237 Nzm (175 ft. lbs.) torque. Install thenut retainer and a new cotter pin (Fig. 7).

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

(7) Install the wheel and tire assembly.(8) Lower the vehicle.

AXLE SHAFT— CARDAN U-JOINT

DISASSEMBLYSingle cardan U-joints are not serviceable. If defec-

tive, they must be replaced as a unit. If the bearings,seals, spider or bearing caps are damaged or worn,replace the complete U-joint.

CAUTION: Clamp only the forged portion of theyoke in the vise. Also, to avoid distorting the yoke,do not over tighten the vise jaws.

(1) Remove the bearing cap retaining snap rings(Fig. 8).

It can be helpful to saturate the bearing capswith penetrating oil prior to removal.

(2) Locate a socket that is larger in diameter thanthe bearing cap. Place the socket (receiver) againstthe yoke and around the perimeter of the bearing capto be removed. Locate a socket that is smaller in di-ameter than the bearing cap. Place the socket (driv-er) against the opposite bearing cap. Position theyoke with the sockets in a vise (Fig. 9).

(3) Compress the vise jaws to force the bearing capinto the larger socket (receiver).

(4) Release the vise jaws. Remove the sockets andbearing cap that was partially forced out of the yoke.

(5) Repeat the above procedure for the remainingbearing cap.

(6) Remove the remaining bearing cap, bearings,seals and spider from the propeller shaft yoke.

CLEANING AND INSPECTION(1) Clean all the U-joint yoke bores with cleaning

solvent and a wire brush. Ensure that all the rustand foreign matter are removed from the bores.

(2) Inspect the yokes for distortion, cracks andworn bearing cap bores.

(3) Replace the complete U-joint if any of the com-ponents are defective.

ASSEMBLY(1) Pack the bearing caps 1/3 full of wheel bearing

lubricant. Apply extreme pressure (EP), lithium-baselubricant to aid in installation.

(2) Position the spider in the yoke. Insert the sealsand bearings. Tap the bearing caps into the yokebores far enough to hold the spider in position.

(3) Place the socket (driver) against one bearingcap. Position the yoke with the socket wrench in avise.

Fig. 8 Axle Shaft Outer U-Joint

Fig. 9 Yoke Bearing Cap Removal


(4) Compress the vise to force the bearing caps intothe yoke. Force the caps enough to install the retain-ing clips.

(5) Install the bearing cap retaining clips.(6) Install the axle shaft, refer to Hub Bearing and

Axle Shaft installation.

AXLE SHAFT— CV-JOINT

HANDLING AND CLEANING PRECAUTIONSExtreme care must be exercised to avoid punctur-

ing or tearing the boots. Also avoid damage to theABS tone ring pressed onto the CV-joint.

The rubber material in shaft boots is not com-patible with oil, gasoline, or petroleum basedcleaning solvents. Do not expose the rubberboots to any of these fluids. Use only soap andwater to clean the rubber boots. After cleaning,the rubber boot must be thoroughly rinsed anddried.

INSPECTIONThe most common failure of CV-joints is torn or

ripped boots and subsequent lubricant loss or con-tamination. Look for lubricant around the exterior ofboot. Check for a punctured or torn boot or retainingclamp loose. If joint was operating satisfactorily andgrease does not appear contaminated, replace boot.When a CV drive shaft is removed from the vehiclefor service, the boot should be properly cleaned. In-spect the boot for cracks, tears and scuffed areas onthe surfaces. If any of these conditions exist boot re-placement is recommended.

If joint is noisy or worn, bypass following dis-assembly and replace entire unit and boot.

DISASSEMBLY(1) Remove retaining clamps from the outer CV

joint and discard. Slide the boot off the outer jointand down the shaft.

(2) Remove the lubricant to expose the joint com-ponents (Fig. 10).

(3) Clamp the shaft in a vise (with soft jaws). Givea sharp tap to the top of the housing to dislodge jointfrom internal circlip. Slide the joint from the shaft.(Fig. 11).

(4) Remove the surplus lubricant. Apply installa-tion alignment marks on the bearing hub, bearingcage and housing with dabs of paint (Fig. 12).

Fig. 10 CV Joint Components

Fig. 11 Joint Removal


(5) Place the stub shaft in a soft-jawed vise toavoid damage to the shaft splines.

(6) Press down on one side of the bearing cage/hubto tilt the cage. This will provide access to a ball atthe opposite side of the cage. If the CV joint is tight,use a hammer and brass drift to loosen the bearinghub. Do not hit the bearing cage with the drift.

(7) Remove the ball from the bearing cage (Fig.13). If necessary, a small pry bar can be used to prythe ball loose from the cage.

(8) Repeat the step above until all six balls are re-moved from the bearing cage.

(9) Tilt the bearing cage and hub to a vertical po-sition to remove (Fig. 14).

(10) Insert one of the bearing hub lands into theadjacent cage window and roll it out of the cage (Fig.15).

INSPECTIONPolished contact surface areas on raceways

and bearing cage spheres are normal. If jointwas noisy or vibrated it should be replaced.

(1) Inspect the lubricant for grit, dirt, water dam-age and metallic particles.

(2) Clean all the components with an appropriatesolvent and dry them with compressed air.

(3) Inspect the ball raceways in the housing for ex-cessive wear or scoring.

(4) Examine the stub shaft splines and threads fordamage.

(5) Inspect the balls for pitting, cracks, scoring andexcessive wear. A dull exterior surface is normal.

(6) Inspect the bearing cage for wear, grooves, rip-ples, cracks and chipping.

(7) Inspect the bearing hub for excessive wear andscoring on ball raceways.

ASSEMBLY(1) Lightly apply lubricating oil to all joint compo-

nents before assembling them.(2) Align the bearing hub, cage and housing ac-

cording to the alignment reference marks.

Fig. 12 Ball Access

Fig. 13 Ball Removal

Fig. 14 Bearing Cage & Hub Removal

Fig. 15 Bearing Hub Removal


(3) Insert one of the bearing hub lands into a bear-ing cage window and roll it into the cage (Fig. 16).Rotate the bearing hub 90° to complete the installa-tion (Fig. 17).

(4) Insert bearing cage/hub into the housing (Fig.18). Rotate the cage/hub 90° to complete the installa-tion. Ensure the tapered edge is facing outward(Fig. 19).

(5) Apply the lubricant included with the replace-ment rubber boot to the ball raceways. Spread the lu-bricant equally between all the raceways. One packetof lubricant is sufficient to lubricate the joint.

(6) Tilt the bearing hub and cage and install theballs in the raceways (Fig. 20).

(7) Install the rubber boot on the axle shaft. En-sure the clamp sealing area is in the grooved sectionof the axle shaft. Install a new clamp.

Fig. 16 Bearing Hub Installation

Fig. 17 Assembled Bearing Cage & Hub

Fig. 18 Bearing Cage & Hub Installation

Fig. 19 Assembly Installed

Fig. 20 Ball Installation In Raceway


(8) Engage the splines and install the joint ontothe shaft. Tap sharply with mallet until seated (Fig.21).

(9) Ensure that the snap ring is properly seated inthe housing. Pull the outer CV joint from the shaft totest, it should not come off.

(10) Install remaining amount of lubricant to cageand balls.

(11) Place the large diameter end of the rubberboot over the edge of the housing. Ensure that theboot is not twisted.

(12) Ensure the clamp sealing area is in thegrooved section of the housing. Install a new clamp.

(13) Install the axle shaft, refer to Hub Bearingand Axle Shaft installation.

STEERING KNUCKLE AND BALL STUDSBall Stud service procedures below require removal

of the hub bearing and axle shaft. Removal and in-stallation of upper and lower ball stud requires useof Tool Kit 6289 (J34503-A).

KNUCKLE REMOVAL(1) Remove hub bearing and axle shaft. Refer to

the Removal procedures in this Group.(2) Remove tie-rod or drag link end from the steer-

ing knuckle arm. Remove the ABS sensor wire andbracket from knuckle.

(3) Remove the cotter pin from the upper ball studnut. Remove the upper and lower ball stud nuts.

(4) Strike the steering knuckle with a brass ham-mer to loosen. Remove knuckle from axle tube yokes(Fig. 22).

UPPER BALL STUD REPLACEMENT(1) Position tools as shown to remove and install

ball stud (Fig. 23).

LOWER BALL STUD REPLACEMENT(1) Position tools as shown to remove and install

ball stud (Fig. 24).

KNUCKLE INSTALLATION(1) Position the steering knuckle on the ball studs.(2) Install and tighten the bottom retaining nut to

108 Nzm (80 ft. lbs.) torque. Install new cotter pins.(3) Install and tighten the top retaining nut to 101

Nzm (75 ft. lbs.) torque. Install new cotter pin.(4) Install the Hub Bearing and Axle Shaft. Refer

to the installation procedure.(5) Install tie-rod or drag link end onto the steer-

ing knuckle arm. Install the ABS sensor wire andbracket to the knuckle, refer to Group 5, Brakes forproper set-up.

Fig. 21 Joint Installation

Fig. 22 Steering Knuckle Removal/Installation


Fig. 23 Upper Ball Stud Remove/Install

Fig. 24 Lower Ball Stud Remove/Install


AXLE BUSHING REPLACEMENTRefer to Axle Bushing Replacement in the Front

Suspension section.

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. 25).

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

pins seated in the locating holes (Fig. 26). 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. 26) and zero the indicator.

CAUTION: Do not spread over 0.38 mm (0.015 in.). Ifthe housing is spread too much, it could be dis-torted or damaged.

(5) Separate the housing a maximum of 0.38 mm(0.015 in.). Measure the distance with the dial indi-cator (Fig. 26).

(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. 27).

(8) Remove the case from housing. Mark or tagbearing cups indicating which side they were re-moved. Remove spreader from housing.

AXLE SHAFT OIL SEALS(1) Remove the inner axle shaft seals with a pry

bay.(2) Install oil seals with Discs 6798 and Turn-

buckle 6797 (Fig. 28). Tighten tool until disc bottomsin housing.

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

with Press C-293PA, Plug C-293-3, Adapter C-293-39(Fig. 29).

Place adapter rings so they do not damagethe bearing cage.

(2) Remove bearing shims from case hubs andmark them (with hub identity) for assembly refer-ence. Record the thickness of the shims.

(3) Clamp the differential case in a vise equippedwith soft jaws. Remove and discard the ring gear

Fig. 25 Bearing Cap Identification

Fig. 26 Spread Differential Housing

Fig. 27 Differential Removal


bolts. Tap the ring gear with a rawhide or plasticmallet and remove (Fig. 30).

(4) Use a drift to remove the pinion gear mateshaft lock pin (Fig. 31).

Fig. 28 Axle Shaft Oil Seal Installation

Fig. 29 Differential Bearing Removal

Fig. 30 Ring Gear Removal

Fig. 31 Mate Shaft Lock Pin Removal


(5) Remove the mate shaft with a drift and ham-mer (Fig. 32).

(6) Rotate the differential side gears and removethe pinion mate gears and thrust washers (Fig. 33).

(7) Remove the differential side gears and thrustwashers.

(8) 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. 34).

(2) Drive out pinion gear from housing with raw-hide or plastic hammer (Fig. 35). Catch the pinionwith your hand to prevent it from falling and being

damaged. This will damage the front bearingrollers and bearing cup. The front bearing andcup must be replaced.

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

(4) Remove oil slinger, front bearing.(5) Remove the front pinion bearing cup and seal

with Remover D-147 and Handle C-4171 (Fig. 36).(6) Remove the rear bearing cup from housing with

Remover D-149 and Handle C-4171 (Fig. 37).(7) Remove the collapsible preload spacer (Fig. 38).(8) Remove the inner bearing from the pinion with

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

the bearing cage.

Fig. 32 Mate Shaft Removal

Fig. 33 Pinion Mate Gear Removal

Fig. 34 Pinion Yoke Removal

Fig. 35 Remove Pinion Gear


(9) Remove the oil slinger (select thickness-produc-tion) from the pinion gear shaft. Record the thick-ness of slinger.

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, do spindry bearings with compressed air. Cup and bearingmust be replaced as matched sets only.

Clean the axle shaft tubes with a stiff wire brushor clean cloth.

Inspect the components for;• 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

Fig. 36 Front Bearing Cup Removal

Fig. 37 Rear Bearing Cup Removal

Fig. 38 Collapsible Spacer

Fig. 39 Inner Bearing Removal


• 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) Install and seat the locking roll pin in the dif-ferential case and mate shaft with a punch and ham-mer (Fig. 40). Peen metal part of case over pin in twoplaces a 180 degrees apart.

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.

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

(4) Install new ring gear bolts and alternatelytighten to 95-122 Nzm (70-90 ft. lbs.) torque (Fig. 41).

(5) Lubricate all differential components with alight coat of grease or hypoid 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. 42). 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 92.1 mm (3.625 inches) for Model 30 axles (Fig.43). The standard depth provides the best teeth con-tact pattern.

Fig. 40 Mate Shaft Pin Installation

Fig. 41 Ring Gear Bolt Installation

Fig. 42 Pinion Gear ID Numbers


THE BUTTON END ON THE PINION GEAR HEADIS NO LONGER A MACHINED-TO-SPECIFICATIONSSURFACE. DO NOT USE THIS SURFACE FOR PIN-ION DEPTH SET-UP OR CHECKING (Fig. 43).

Compensation for depth variance is achieved by a se-lected thickness oil slinger (production) or shims (ser-vice). The slinger is placed between the inner pinionbearing cone and gear head (Fig. 44). The shim pack isplaced under the inner (rear) bearing cup. To changethe pinion adjustment, shims are available in thick-nesses of 0.003, 0.005, and 0.010 inch. If equipped, theoil slinger or baffle must be measured and thethickness included with the total shim pack.

If a new gear set is being installed, note thenumber etched into both pinion gears. Add orsubtract the thickness of original depth shims

to compensate for the difference in depth vari-ances. Refer to the Depth Variance charts.

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 (0.10 mm). Add this amount to the originalshim. Or if the old pinion is (-) 3 and the new pinionis (-) 2, intersecting figure is (-) 0.001 inch (0.025

Fig. 44 Shim and Slinger Location

PINION GEAR DEPTH VARIANCE

Fig. 43 Pinion Gear Head


mm). Subtract this amount from original shim. Referto the Pinion Gear Depth Variance Chart.

DIFFERENTIAL AND PINION MEASUREMENT

DIFFERENTIAL ZERO END PLAYMEASUREMENT

(1) Place Master Differential Bearing D-134(D-348) on the case hubs (Fig. 45).

(2) Install a pilot stud at the right side of housing.Attach Dial Indicator to the pilot stud. Load indica-tor plunger against the back of the ring gear (Fig.46).

(3) Insert a small pry bar between the bearing capand left side of differential case. Pry the case as faras possible to right side (Fig. 46). Zero the dial indi-cator pointer.

(4) Pry the case to left side and record the traveldistance.

The measurement above is the shim thicknessnecessary for case zero end-play. The totalthickness will be determined during the ringgear backlash adjustment.

(5) Remove indicator and pilot stud.

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

Measurements are done with pinion cups and pin-ion bearings installed in housing. Take measure-ments with Pinion Gauge Set 6774, Pinion Block6733 and Dial Indicator C-3339 (Fig. 47).

Fig. 45 Master Bearing Tools On Hubs

Fig. 46 Differential Case End Play Measurement

Fig. 47 Pinion Gear Depth Gauge Tools


(1) Assemble Pinion Gauge Set, Pinion Block andpinion bearings. Install assembly into differentialpinion gear bore and hand tighten cone (Fig. 48).

(2) Place Arbor Disc 6732 on Arbor D-115-3 and po-sition in the bearing cradles (Fig. 49). 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. 50). Record the longesttravel distance, whether inward (-) or outward (+),indicated by the pointer.

The plunger travel indicated, plus or minusthe variance etched in the gear is the requiredthickness for the depth shims.

(5) Measure the thickness of each depth shim witha micrometer. Then combine the shims needed for to-

tal shim pack thickness. Include oil slinger or baf-fle thickness with the total shim packthickness.

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

PINION GEAR ASSEMBLY/INSTALLATION(1) Place the needed shim pack thickness in the

pinion gear rear bearing bore (service only). Installthe bearing cup with Installer D-146 and DriverHandle C-4171 (Fig. 51). Ensure cup is correctlyseated.

(2) Install the pinion front bearing cup with In-staller D-144 and Handle C-4171 (Fig. 52).

Fig. 48 Pinion Height Block

Fig. 49 Gauge Tools In Housing

Fig. 50 Pinion Gear Depth Measurement

Fig. 51 Pinion Rear Bearing Cup Installation


(3) If used, place the oil slinger on the pinion gear.Install the rear (inner) bearing on the pinion gearwith Installer W-262 (Fig. 53).

(4) Install a new collapsible preload spacer on pin-ion shaft. (Fig. 54).

(5) Install pinion front bearing and oil slinger. Ap-ply a light coating of gear lubricant on the lip of pin-ion seal. Install seal with Installer D-163 and HandleC-4171 (Fig. 55).

Fig. 52 Pinion Front Bearing Cup Installation

Fig. 53 Rear Bearing Installation

Fig. 54 Collapsible Preload Spacer

Fig. 55 Pinion Seal Installation


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

C-3281 (Fig. 56).

(8) Install the yoke washer AND A NEW NUT onthe pinion gear. Tighten the nut to 216 Nzm (160ft. lbs.).

CAUTION: Never loosen the pinion gear nut to de-crease the pinion gear bearing preload torque. If thespecified preload torque exceeds 352 N zm (260 ft.lbs.) a new collapsible spacer must be installed.The torque sequence will have to be repeated.

(9) Use Flange Wrench C-3281 to retain the yoke(Fig. 57). Slowly tighten the nut in small incrementsuntil the rotating torque is achieved. Measure thepreload torque frequently to avoid over-tight-ening the nut.

(10) Check bearing preload torque with an inchpound torque wrench (Fig. 58). The torque necessaryto rotate the pinion gear should be;• Original Bearings: 1 to 3 Nzm (10 to 20 in. lbs.).• New Bearings: 1.5 to 4 Nzm (15 to 35 in. lbs.).

DIFFERENTIAL SHIM PACK MEASUREMENT ANDADJUSTMENT

(1) Place Master Differential Bearing D-134(D-348) on the case hubs.

(2) Place Differential assembly in the housing. As-semble Differential bearing caps.

(3) Install a pilot stud at the left side of housing.Attach Dial Indicator to housing. Load the indicatorplunger against the back of the ring gear (Fig. 59).

Ensure ring and pinion gear teeth are tightlymeshed. Zero the indicator.

(4) Insert a small pry bar between the bearing capand left side of differential case. Pry the case as faras possible to right side (Fig. 60). Zero the dial indi-cator pointer.

(5) Repeat the measurement several times to checkconsistency. Record the travel distance.

The measurement above shows shim thick-ness necessary to eliminate ring gear backlash.Subtract this thickness from case zero end-play

Fig. 56 Pinion Yoke Installation

Fig. 57 Tightening Pinion Nut

Fig. 58 Check Pinion Gear Torque


shim thickness (Fig. 60). The shims must beplaced at the ring gear side between the caseand bearing.

(6) Remove indicator and pilot stud.(7) Remove the differential case from housing.(8) Remove the master bearing tools from the dif-

ferential case hubs.(9) Position the backlash shims (with determined

thickness) on case hub (ring gear side). Install bear-

ing on the hub with Bearing Installer C-3716A andDriver Handle C-4171 (Fig. 61).

(10) Position the remaining zero end-play shims onhub at opposite side of case. Include an additional0.015 in. (0.38 mm) thick shim on this hub. This willprovide the required differential bearing preload.

(11) Install bearings on hubs with InstallerC-3716A and Handle C-4171 (Fig. 61).

(12) Match each bearing cup with bearing (origi-nal). Install the cups on the bearings.

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

pins seated in the locating holes (Fig. 62). Install theholddown clamps and tighten the tool turnbuckle fin-ger-tight.

Fig. 59 Shim Pack Measurement

Fig. 60 Shim Pack Calculations

Fig. 61 Differential Bearing Installation

Fig. 62 Spread Differential Housing


(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. 63) 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. 62).

(4) Remove the dial indicator.(5) Install case in the housing. Tap the differential

case to ensure the bearings are fully seated. Removethe spreader.

(6) Install the bearing caps at their original loca-tions. Tighten the bearing cap bolts to 61 Nzm (45 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. 63).

The ring gear backlash must be within 0.005 -0.008 inch (0.12 - 0.20 mm). It cannot vary morethan 0.002 inch (0.05 mm) between the pointschecked.

If backlash must be adjusted, transfer shims fromone side of carrier to the other side. Adjust the back-lash accordingly (Fig. 64). DO NOT INCREASETHE TOTAL SHIM PACK THICKNESS, EXCES-SIVE BEARING PRELOAD AND DAMAGE MAYOCCUR.

If the mesh and backlash steps have been followedin the procedures above, good gear teeth contact pat-terns should exist.

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 drive and coast side of the ring gear.

(3) Rotate the ring gear several revolutions in bothdirections while a load is being applied. Insert a prybar 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.

(4) Note patterns in compound. Refer to (Fig. 65)for interpretation of contact patterns and adjust ac-cordingly.

Fig. 63 Ring Gear Backlash Measurement

Fig. 64 Backlash Shim Adjustment


Fig. 65 Gear Tooth Contact Patterns


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

stallation in 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. 66).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 with 41 Nzm (30 ft. lbs.) torque.

CAUTION: Overfilling the differential can result inlubricant foaming and overheating.

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

(5) Install the fill hole plug and tighten to 34 Nzm(25 ft. lbs.) torque.

AXLE SPECIFICATIONS

MODEL 30 AXLEAxle Type ........................................................HypoidLubricant................SAE Thermally Stable 80W-90Lube Capacity ................................1.18 L (2.5 pts.)Axle Ratio....................................................3.55 3.73DifferentialBearing Preload..........................0.38 mm (0.015 in.)

Ring GearDiameter .....................................18.09 cm (7.125 in.)Backlash....................0.12-0.20 mm (0.005-0.008 in.)Pinion Std. Depth ...................92.1 mm (3.625 in.)Pinion Bearing Preload TorqueOriginal Bearing ..................1-2 Nzm (10-20 in. lbs.)New Bearing......................1.5-4 Nzm (15-35 in. lbs.)

TORQUE SPECIFICATIONS

FRONT SUSPENSION COMPONENTS

DESCRIPTION................................................TORQUEShock AbsorberUpper Nut....................................23 Nzm (17 ft. lbs.)Lower Nut .................................28 Nzm (250 in. lbs.)Suspension Arm UpperNuts ..............................................75 Nzm (55 ft. lbs.)Suspension Arm LowerNuts ............................................115 Nzm (85 ft. lbs.)Stabilizer BarClamp Bolt...................................54 Nzm (40 ft. lbs.)Link Upper Nut ..........................36 Nzm (27 ft. lbs.)Link Lower Bolt ..........................95 Nzm (70 ft. lbs.)Track BarBall Stud Nut..............................81 Nzm (60 ft. lbs.)Axle Bracket Bolt........................75 Nzm (55 ft. lbs.)Track Bar Bracket

Bolts............................................121 Nzm (90 ft. lbs.)Nut..............................................121 Nzm (90 ft. lbs.)Support Bolts...............................95 Nzm (70 ft. lbs.)

MODEL 30 AXLE

DESCRIPTION................................................TORQUEFill Hole Plug ...........................34 Nzm (25 ft. lbs.)Diff. Cover Bolt ........................41 Nzm (30 ft. lbs.)Bearing Cap Bolt .....................61 Nzm (45 ft. lbs.)Ring Gear Bolt .............95-122 Nzm (70-90 ft. lbs.)Axle Nut .................................237 Nzm (175 ft. lbs.)Wheel Brg. Bolt ......................102 Nzm (75 ft. lbs.)Lower Ball Stud .....................108 Nzm (80 ft. lbs.)Upper Ball Stud .....................101 Nzm (75 ft. lbs.)ABS Sensor Bolt ......................11 Nzm (96 in. lbs.)

Fig. 66 Typical Housing Cover With Sealant


95ZJ_2.PDF

Automotive

tool turnbuckle

fill hole

contact pattern

scribe alignment

headon long

tool dowelpins

clamp sealing

frame rail