chrysler dakota part3

7/28/2019 chrysler dakota part3

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REAR SUSPENSION AND AXLES

CONTENTS

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7 1/4 and 8 1/4INCHAXLE . . . . . . . . . . . . . . . 12AXLE NOISE/VIBRATION DIAGNOSIS . . . . . . . . . 8AXLE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . 36GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1

REAR SUSPENSION2WD AND 4WDVEHICLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

TORQUE SPECIFICATIONS . . . . . . . . . . . . . . . . 36TRAC-LOC DIFFERENTIAL . . . . . . . . . . . . . . . . . 30

GENERAL INFORMATION

SUSPENSIONDakota rear suspensions are comprised of;

Drive axle L eaf springs

Dual-action shock absorbers

J ounce bumpers (used to limit the travel of the

suspension)

The rear suspension design uses semi-elli ptic

multi-leaf springs and a solid drive axle. The forward

end of the springs are mounted to the frame rail

hangers through rubber bushings. T he bushings iso-

late road noise as the springs move. The rearward

end of the springs are attached to the frame by the

use of shackles. Again the spring and shackles use

rubber bushings to isolate road noise. The shackles

allow the springs to change their length as the vehi-

cle moves over various road conditions. The spring

and axle travel is limited through the use of rubber

bumpers mounted on the frame.

Suspension components that use rubber bushings

should be tightened with the vehicle at the normal

height. Rubber bushings must never be lubricated.

The springs are attached to the axle pads with U-

bolts and plates. The springs use a center bolt that

aligns and holds the spring leafs in position. The bolt

is also used to locate the spring assembly to the axle

pad which is welded to the axle shaft tubes.

Ride control i s accomplished through the use of du-al-action shock absorbers. The shocks dampen the

jounce and rebound as the vehicle travels over vari-ous road conditions. The top of the shock absorbersare bolted to the frame crossmember. The bottom ofthe shocks are bolted to the axle bracket.

AXLESThe 7 1/4 or 8 1/4 I nch axle housings consist of a

cast iron center section. They also have two steel axleshaft tubes that are pressed into and welded to thedifferential housing.

The cover provides a means for inspection and ser-

vice without removing the axle from the vehicle.

A small, gear ratio identification tag is attached to

the housing cover.

The rear wheel anti-lock (RWAL ) brake speed sen-

sor is attached to the top of the differential housing

(Fi g. 1). A seal is located between the sensor and the

wire harness connector. The seal must be in-place

when the wire connector is connected to the

sensor. The RWAL brake exciter ring is press-fitted

onto the differential case against the flange.

Fig. 1 Rear Axle RWAL Sensor

REAR SUSPENSION AND AXLES 3 - 1


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IDENTIFICATION

The diameter of the ring gear can be determined

from the size of the axle shaft tubes.

The 7 1/4 I nch axle has shaft tubes that are 2.5-

inch (63.5-mm) diameter at the i nner end. The outer

end is 3.0-inch (76.2-mm) diameter

The 8 1/4 I nch axle has axle shaft tubes that have

a 3.0-inch (76.2-mm) diameter at both endsThe axle differential covers can be used for identi-

fication (Fig. 2, 3).

Both axle types are equipped with a remote vent

fitting.

7 1/4 I nch axle, the fitting is on the right axle

shaft tube

8 1/4 Inch axle, the fitting is on the left axle shaft

tube

STANDARD DIFFERENTIAL OPERATIONThe differential gear system divides the torque be-

tween the axle shafts. I t allows the axle shafts to ro-

tate at different speeds when turni ng corners.

Each differential side gear is splined to an axle

shaft. The pinion gears are mounted on a pinion

mate shaft and are free to rotate on the shaft. The

pinion gear is fitted in a bore in the differential case

and is positioned at a right angle to the axle shafts.

I n operation, power flow occurs as follows: The pinion gear rotates the r ing gear The ring gear (bolted to the differential case) ro-tates the case The differential pinion gears (mounted on the pin-ion mate shaft in the case) rotate the side gears The side gears (splined to the axle shafts) rotatethe shafts

During straight-ahead driving, the differential pin-ion gears do not rotate on the pinion mate shaft. T hisoccurs 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. 4).

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 becomes effective allowingthe axle shafts to turn at unequal speeds (Fig. 5). I nthis instance, the input torque applied to the piniongears is not divided equally. The pinion gears now ro-tate around the pinion mate shaft in opposite direc-

Fig. 2 Differential Cover 7 1/4 Inch Axle

Fig. 3 Differential Cover 8 1/4 Inch Axle

Fig. 4 Differential OperationStraight-Ahead Driving

3 - 2 REAR SUSPENSION AND AXLES


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tions. This allows the side gear and axle shaftattached to the outside wheel to rotate at a fasterspeed.

Fig. 5 Differential OperationOn Turns



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REAR SUSPENSION2WD AND 4WD VEHICLES

SPRINGAND SHOCKDIAGNOSISA noise from the shock absorber or spring bushings

can be produced if movement between the rubberbushings and the metal occurs. This noise can usu-ally be stopped by tightening the nuts. I f the noise

persists, inspect for damaged and worn bushings. Re-pair as necessary.The shock absorber bushings do not require any

type of lubrication. Do not lubricate the bushings toreduce bushing noise. Grease or mineral oil-base lu-bricants will deteriorate the bushing rubber.

The shock absorbers are not refillable or adjust-able. I f 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.

The spring eye and shock absorber bushings do not

require any type of lubrication. Do not attempt tostop spring bushing noise by lubricating them.Grease and mineral oil-base lubricants will deterio-rate the bushing rubber.

I f the vehicle is used for severe, off-road operation,the springs should be examined regularl y. Check forbroken and shifted components.

VEHICLE LOADING AND WEIGHT DISTRIBUTIONA vehicle should always be loaded so the vehicle

weight center-line is located immediately forward of

the rear axle. Correct vehicle loading provides proper

front tire-to-road contact. This results in maximum

vehicle handling stability and safety. I ncorrect vehi-cle weight distribution can cause excessive tire wear,

spring fatigue, and erratic steering. Refer to Spring

and Shock Absorber Diagnosis chart for further infor-

mation.

SHOCKABSORBER

REMOVAL

(1) Raise and support the vehicle.

(2) Remove the shock absorber lower nut and bolt

from the axle bracket (Fig. 1, 2).

(3) R emove the shock absorber upper nuts and

bolts from the frame crossmember bracket (F ig. 1, 2).

Remove the shock absorber.

INSTALLATION

(1) I nstall the shock absorber and upper fasteners

on the frame bracket (Fig. 1, 2).

SPRING AND SHOCK ABSORBER DIAGNOSIS



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(2) I nstall the shock absorber lower eye into the

axle bracket. I nstall the bolt and nut and tighten to

81 Nm (60 ft. lbs.) torque.

(3) Tighten the upper bracket nuts to 27 N

m (20ft. lbs.) torque.

LEAF SPRINGS

CAUTION: The rear of the vehicle must be lifted

only with a jack or hoist. The lift must be placed un-

der the frame rail crossmember located aft of the

rear axle. Use care to avoid bending the side rail

flange.

REMOVAL

(1) Raise the vehicle at the frame.(2) Use a hydraulic jack to relieve the axle weight.

(3) Remove the wheel and ti re.

(4) Remove the nuts, the U-bolts and spring

bracket from the axle (Fig. 1, 2).

(5) Remove the nut and bolt that attaches the

spring rear eye to the shackle (Fig. 1, 2).

(6) Remove the nut and bolt from the spring front

eye (Fig. 1, 2).

(7) Remove the spring fr om the vehicle.

INSTALLATION

(1) I f removed, install the spring shackle on the

spring finger tight (F ig. 1, 2).

(2) Position the spring on the rear axle pad. Makesure the spring center bolt is inserted in the pad lo-

cating hole (Fig. 1, 2). I f 2WD, ensure the parking

brake cable guide is properly positioned.

(3) Ali gn the spring front eye with the bolt hole in

the rail front bracket. I nstall the spring eye bolt and

nut (Fig. 1, 2). Tighten the spring eye nut finger-

tight.

(4) Align the spring shackle eye with the bolt hole

in the rail rear bracket. I nstall the bolt and nut (Fig.

1, 2). Tighten the spring shackle eye nut finger-tight.

(5) I nstall the spring seat (2WD only), U-bolts,

spring bracket, replacement washers and nuts (Fig.1, 2). Tighten the nuts until the washers are com-

pressed against the spring bracket.

(6) R emove the support stands from under the

frame rails. L ower the vehicle until the springs are

supporting the weight of the vehicle. Tighten the U -

bolt nuts (Fig. 1, 2):

2WD vehicles88 N m (65 ft. lbs.) torque


(7) Tighten the spring eye pivot bolt nut and all

shackle nuts to 88 N m (65 ft. lbs.) torque (Fig. 1, 2).

(8) I nstall the wheel and tire.

Fig. 1 Spring & Shock Absorber2WD



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SPRINGLEAF REPLACEMENT(1) Remove the spring from the vehicle. I f neces-

sary, refer to the removal procedure.

(2) Remove the alignment cli ps.(3) Clamp the spring in a vise and remove the nut

and the center bolt (Fi g. 3).

(4) I nsert a long drift or punch into the center bolt

hole and slowly release the vise jaws.

(5) Remove the spring from the vise. Replace the

broken/defective leaf. I nsert a long drift or punch

into the spring center bolt hole.

(6) Position the spring between vise jaws andslowly tighten the vise jaws. K eep the spring leaves

aligned with the long drift or punch.

(7) Remove the drift from the spring center bolt

hole. I nstall a replacement center bolt and nut (Fig.

3).

(8) Tighten the nut to 40 N m (30 ft. lbs.) torque.

An alternate way is to tighten the nut until the

spring has no gaps between the leaves (maximum of

54 Nm/40 ft. lbs. torque).

(9) I nstall the alignment clips.

(10) Pi n the center bolt with a hammer to prevent

the nut from backing off.

(11) I nstall the spring in the vehicle. I f necessary

refer to the installation procedure.

LEAF SPRINGEYE BUSHINGREPLACEMENT(1) Assemble tools shown (Fig. 4). Tighten the nut

located at the socket wrench end of the threaded rod

until the bushing i s forced out.

(2) Assemble and align the bushing installation

tools.

Fig. 2 Spring & Shock Absorber4WD

Fig. 3 Leaf Spring Disassembly



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(3) Align the bushing with the spring eye and

tighten the nut located at the socket wrench end of

the threaded rod. Tighten until the bushing is forcedinto the spring eye.

The bushing must be centered in the springeye. The ends of the bushing must be flushwithin the end surfaces of the spring eye.

Fig. 4 Spring Eye Bushing Removal



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AXLE NOISE/VIBRATION DIAGNOSIS

INDEX

page page

Driveline Snap . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Gear and Bearing Noise . . . . . . . . . . . . . . . . . . . . . 8General Information . . . . . . . . . . . . . . . . . . . . . . . . 8Limited Slip Differential . . . . . . . . . . . . . . . . . . . . . . 9

Low Speed Knock . . . . . . . . . . . . . . . . . . . . . . . . . . 9Rear Axle Alignment . . . . . . . . . . . . . . . . . . . . . . . . 9Vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

GENERAL INFORMATIONAxle bearing problem conditions are usually caused

by:

I nsufficient or incorrect lubricant

Foreign matter/water contaminati on

I ncorrect bearing preload torque adjustment

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 bearing

surfaces. T his will result in noisy operation af-

ter repair.

Axle gear problem conditions are usually the result

of:

I nsufficient lubrication

I ncorrect or contaminated lubricant

Overloading (excessive engine torque)

I ncorrect clearance or backlash adjustment

I nsufficient lubrication is usually the result of a

housing cover leak. I t can also be from worn axle

shaft or pinion gear seals. Check for cracks or porous

areas in the housing or tubes.

Using the wrong lubricant or over filling will cause

overheating and gear failure. Gear tooth cracking

and bearing spalling are indicators of this.

Axle component breakage is most often the result

of:

Severe overloading

I nsufficient lubricant

I ncorrect lubricant

I mproperl y tightened components

Common causes of overloading is from full-throttle

acceleration. Overloading happens when towing

heavier-than-recommended loads. Component break-age can occur when the wheels are spun excessively.

I nsufficient or incorrect lubricants contribute to

breakage through overheating. L oose differential

components can also cause breakage.

I ncorrect bearing preload or gear backlash will not

result in component breakage. Mis-adjustment will

produce enough noise to cause service repair before a

failure occurs. I f a mis-adjustment condition is not

corrected, component fail ure can result.

GEAR AND BEARINGNOISE

GEAR NOISE

Axle gear noise can be caused by insufficient lubri-

cant. I ncorr ect backlash, tooth contact, or worn/dam-

aged gears can cause noise.

Gear noise usually happens at a specific speed

range. The range i s 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 the

speed range where the noise is the greatest. Shift

out-of-gear and coast through the peak-noise range.

I f the noise stops or changes greatly, check for insuf-

ficient lubricant. I ncorrect ring gear backlash, or

gear damage can cause noise changes.Differential side and pinion gears can be checked

by turning the vehicle. They usually do not causenoise in straight-ahead driving. These gears areloaded during vehicle tur ns. I f 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 NOISE

The 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 wil l be higher because i t rotates at afaster rate. Drive the vehicle and load the differen-

tial. I f bearing noise occurs the pinion rear bearing isthe source of the noise. I f 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 i ssimilar to pinion bearing. The pitch of differentialbearing noise i s also constant and varies only withvehicle speed.

Axle shaft bearings produce noise and vibrationwhen worn or damaged. T he noise generally changeswhen the bearings are l oaded. Road test the vehicle.Turn the vehicle sharply to the l eft and to the right.



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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 KNOCKL ow speed knock is generally caused by a worn

U-joint or by worn side-gear thrust washers. A worn

pinion 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 L oose wheel lug nuts Worn U-joint L oose spring clamp bolts L oose/broken springs Damaged axle shaft bearings

L oose 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 accessori es, bracketsand drive belts.

Al l driveline components should be examined be-fore starting any repair.

Refer to Group 22, Wheels and Tires for additionalinformation.

DRIVELINESNAPA snap or clunk noise when the vehicle is shifted

into gear (or the clutch engaged), can be caused by: High engine idle speed L oose engine/transmission/transfer case mounts Worn U-joints L oose spring mounts L oose 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.I nstruct the helper to shift the transmission intogear. L isten for the noise, a mechanics stethoscope ishelpful in isolating the source of a noise.

REAR AXLE ALIGNMENT

MEASUREMENT

The following procedure can be used to determineif 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 at

the center of each tire tread for use as reference

marks.

(3) Rotate the rear wheels until both reference

marks face the front of the vehicle. Measure the dis-

tance between the outside edges of the two pieces of

tape. Record this measurement as the front of tire

(FTR) measurement.(4) Rotate the rear wheels until both reference

marks face the rear of the vehicle. Measure the dis-

tance between the outside edges of the two pieces of

tape. Record this measurement as the r ear of tire

(RTR) measurement.

(5) Subtract the (RTR) measurement from the

(FTR) measurement to obtain the amount of wheel

toe. The acceptable rear wheel toe-in position is 1/16

inch (1.6 mm) to 3/16 inch (4.8 mm) toe-out.

(6) Rotate the rear wheels until the reference marks

are facing downward. Measure the distance between the

outside edges of the two pieces of tape. Record this mea-surement as the bottom of tire (BTR) measurement.

(7) Average the (FTR) and the (RTR) distance mea-

surements. Subtract the (BTR) measurement from

this average distance to obtain the camber. The ac-

ceptable amount of camber is 1/16 i nch to 3/32 i nch

(1.6 to 2.4 mm).

(FTR + RTR) DIVIDED BY 2 (TWO) MINUS

BTR EQUALS CAMBER

If the (BTR ) distance measurement is less

than the average FTR and RTR distance mea-

surement, the camber will be positive ( + ). If

the (BTR) distance measurement is greater

than the average FTR and RTR distance, the

camber will be negative ( - ).

I f the toe position or camber is not acceptable, a bent

or deformed rear axle shaft i s most likely the cause.

LIMITED SLIP DIFFERENTIALUnder normal traction conditions, engine torque is

divided evenly. With low-traction surfaces, engine

torque is transferred to the wheel with the most tire

traction. When diagnosing a limited-slip differential

problem condition, the wheel with the least traction

can continue spinning.

The most common problem is a chatter noise whenturning corners. Check for incorrect or contaminated

lubricant. Replace the gear lubricant if necessary.

With Trac-Loc differentials add a container of

fri ction modifier when lubricant is changed.

This will correct the condition in most instances. I f

the chatter persists, clutch damage could have occurred.

After changing the lubricant, drive the vehicle and

make 10 to 12 slow, figure-eight turns. This maneu-

ver will pump lubricant through the clutches.



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SERVICE DIAGNOSIS



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SERVICE DIAGNOSIS (CONTD)



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7 1/4 and 8 1/4 INCH AXLE

INDEX

page page

Axle Shaft, Seal and Bearing Service . . . . . . . . . . 15Differential Service . . . . . . . . . . . . . . . . . . . . . . . . 19Drive Axle Assembly Replacement . . . . . . . . . . . . . 12General Information . . . . . . . . . . . . . . . . . . . . . . . 12Lubricant Change . . . . . . . . . . . . . . . . . . . . . . . . . 15

Lubricant Specifications . . . . . . . . . . . . . . . . . . . . . 12Pinion Depth Measurement and Adjustment with

Gauge Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Pinion Seal Replacement . . . . . . . . . . . . . . . . . . . 17

GENERAL INFORMATIONThe 7 1/4 i nch and 8 1/4 i nch rear axle consists of a

cast iron housing. Tubes are pressed into and welded

to the housing to form a one-piece axle housing.

The integral housing hypoid gear design, has the

pinion set below the centerline of the ring gear.

The axle uses a vent hose to relieve internal pres-

sure caused by lubricant vaporization and expansion.The axles are equipped with semi-floating axle

shafts, meaning that loads are supported by the axle

shaft and bearings. The axle shafts are retained by

C-clips i n the differential side gears.

The axles are equipped with RWAL brake sensors.

The sensor is attached to the differential housing and

the exciter ring is pressed on the differential carrier.

Use care when removing the differential as N OT to

damage the sensor.

The removable cover provides a means for inspec-

tion and servicing the differential.

The axles have the gear ratio listed on a tag. The

tag is attached to the housing cover.

The differential case is a one-piece design. The dif-

ferential pinion mate shaft is retained with a

threaded roll pin. Differential bearing preload and

ring gear backlash is adjusted by the use of threaded

adjusters. The adjusters are located between the dif-

ferential bearing cups and housing tubes. Pinion

bearing preload is set and maintained by the use of a

collapsible spacer.

PINION GEAR DEPTH MEASUREMENT WITH

GAUGE SET C-3715-B is used when;

The axle/differential housing is being replaced

The original pinion depth shim pack is lost or mis-placed

Replacing the differential case

Replacing pinion and differential bearings

LUBRICANTSPECIFICATIONSMulti-purpose, hypoid gear lubricant should be

used for the 7 1/4 inch and 8 1/4 inch rear axles. The

lubricant should have M I L -L-2105C and API GL 5

quality specifi cations. M opar Hypoid Gear L ubricant

conforms to both of these specifications.

The factory installed lubricant for the 7 1/4 i nch

and 8 1/4 inch rear axles is SAE 80W 90 gear lubri-

cant

The factory installed lubricant quantity7 1/4 inch, 461 fluid oz..8 1/4 Inch, 701 fluid oz..Refer to Group 0, L ubrication and Maintenance for

additional information.

CAUTION: If axle is submerged in water, lubricant

must be replaced immediately to avoid possiblepremature axle failure.

DRIVE AXLE ASSEMBLY REPLACEMENTI t is not necessary to remove the complete axle

from the vehicle for routine or differential service. I fthe differential housing or axle shaft tubes are dam-aged, the complete axle can be removed and in-stalled.

REMOVAL(1) Raise the vehicle to a comfortable working

height that will permit support stands to be installedat the front of the rear springs.

(2) Block the brake pedal in the up (non-depressed)position with a wooden block.

(3) Remove the wheel and tire. Do not removethe brake drum retaining clips or the drums.

(4) Disconnect the brake fluid tube fittings fromthe wheel cylinders. Cap the fittings to prevent lossof brake fluid.

(5) Remove the vent hose from the brake tee nip-ple.

(6) Remove the brake tee bolt. Carefully detachthe brake fluid tubes from the clips. Disconnect theRWAL brake sensor.

(7) Disconnect the parking brake cables. Mark theU-joint, pinion yoke, and pini on shaft for reference.

(8) Di sconnect the drive shaft from the pinionyoke. Secure the drive shaft in an upright position toprevent damage to the rear U-joint.

(9) Remove the shock absorber lower nuts andbolts. Remove the rear spring U-bolts and springbrackets.

(10) Remove the axle assembly from the vehicle.



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Fig. 1 7 1/4 Inch Axle



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Fig. 2 8 1/4 Inch Axle



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(11) Wash and clean the outer surface of the hous-

ing and axle shaft tubes. Use an appropriate cleaning

solution and dry the surface with compressed air.

INSTALLATION

(1) Support the vehicle at the front of the rear

springs. Position the spring pads on the parking

brake cable guides (2WD vehicles) or against thespring center bolts (4WD vehicles).

Ensure the spring center bolts and holes in

the spring pads are correctly aligned.

(2) I nstall the spring U-bolts, brackets and nuts.

I nstall the shock absorber lower bolts and nuts.


4WD vehicles149 Nm (110 ft. lbs.) torque

(3) Tighten the spring U-bolt nuts finger-tight.

Tighten the shock absorber nuts to 81 Nm (60 ft.

lbs.) torque.

(4) Connect the parki ng brake cables.

(5) Remove the block from the brake pedal.

(6) Connect the brake tube fittings to the wheel

cylinders, bleed and adjust the brakes.

(7) Attach the brake tubes to the clips.

(8) I nstall the brake tee bolt. Tighten it to 14 Nm

(10 ft. lbs./125 i n. lbs.) torque.

(9) Connect the vent hose to the brake tee nipple.

(10) I nstall the drive shaft with the installation

reference marks aligned. Tighten the U-joint yoke

clamp screws to 19 Nm (14 ft. lbs./170 in. lbs.)

torque.

(11) I nstall the wheel and tire.

(12) Adjust the hoist so the vehicle is in a level po-

sition. Check the differential housing lubricant level.I f necessary, add Mopar Hypoid Gear L ubricant to

the corr ect level.

LUBRICANTCHANGEThe gear lubricant will drain quicker if the vehicle

has been recently driven.


(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 cover

surfaces. Use solvent to clean the mating surfaces.

(6) Apply a bead of Mopar Silicone Rubber Sealant

to the housing cover (Fig. 3). 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.

(7) I nstall the cover and any identification tag.

Tighten the cover bolts in a criss-cross pattern to 47

Nm (35 ft. lbs.) torque.

(8) Refill the differential with Mopar Hypoid Gear

L ubricant within 13 mm (1/2 in.) below the fill plug

hole.

Trac-Loc (limited slip) Differentials; must have

(friction modifier) added after service.

(9) I nstall the fill hole plug and lower the vehicle.

LI MITE D SLIP DIFFE RENTIAL vehicles shouldbe road tested by making 10 to 12 slow figure-eight

turns. This maneuver will pump the lubricant

through the cones to eliminate a possible chatter

noise complaint.

AXLESHAFT, SEAL AND BEARINGSERVICE

CAUTION: When rear axle service is necessary,

both rear wheels must be raised off the surface so

that they are free to rotate. Be cautious when the

tires are being rotated by the engine or by other

means.

CAUTION: If equipped with a Trac-Loc differential,

do not rotate either axle shaft unless both are prop-

erly in-place. Rotation of one axle shaft without the

other being installed can result in misalignment of

the side gears/splines. This will necessitate side

gear re-alignment before the axle shaft can be in-

stalled.

Fig. 3 Typical Housing Cover With Sealant



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AXLE SHAFT REMOVAL


(2) Remove the wheel and ti re.

(3) Remove the brake drum.

(4) Cl ean all the foreign material from housing

cover area.

(5) L oosen the housing cover bolts. Drain the lubri-

cant from the housing. Remove the housing cover.(6) Rotate the differential case so that the pinion

mate gear shaft lock screw i s accessible. Remove the

lock screw and the pinion mate gear shaft from the

case (Fig. 4).

(7) Push the axle shaft in toward the center of the

vehicle. Remove the axle shaft C-clip lock from the

axle shaft (Fig. 5).

(8) Remove the axle shaft. Use care to prevent

damage to the axle shaft bearing, which will remain

in the axle shaft tube.

(9) I nspect the axle shaft bearing contact surface

area for indications of brinelling, spalling, and pit-

ting.

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

The normal appearance (from roller bearing

contact) will be a dull gray surface area that

could appear slightly dented.

SEAL AND BEARING REMOVAL

(1) Remove the axle shaft seal with a small pry

bar.

(2) Remove the bearing if it appears damaged or

the axle shaft shows any of the conditions described

above.

(3) Remove the bearing with Remover C-4167 (F ig.

6). Attach Slide Hammer C-637 to the end of the re-

moval tool.

(4) I nspect the axle shaft tube bore for roughness

and burrs. Remove as necessary.

CAUTION: Inspect the housing bore for burrs. Re-

move them if they exist.

BEARING AND SEAL INSTALLATION

Do not install the original axle shaft seal. Al-ways install a new seal.

(1) Wipe the bore in the axle shaft tube clean.(2) I f the original bearing is not reusable, i nstall a

new bearing. P lace the axle shaft bearing on the pilotof Bearing I nstaller C-4198 and Handle C-4171.

Fig. 4 Pinion Mate Shaft Lock Screw

Fig. 5 Axle Shaft C-Clip Lock

Fig. 6 Axle Shaft Bearing Removal



17/36

CAUTION: DO NOT use the new axle shaft seal to

position or seat the bearing in the axle shaft bore.

(3) I nsert the bearing into the tube. Ensure thatthe bearing is not cocked and is seated firmly againstthe tube shoulder.

(4) I nstall the new axle shaft seal (Fig. 7) with I n-

staller C-4203 and H andle C-4171.

(5) When the tool contacts the end of the tube(face), the seal will be at the correct position anddepth.

AXLE SHAFT INSTALLATION

(1) L ubricate the bearing bore and seal lip. I nsertthe axle shaft and engage the splines with the sidegear. Use care to prevent the shaft splines fromdamaging the axle shaft seal lip.

(2) I nsert the C-clip lock in the recessed groove(Fig. 2). Push the axle shaft outward to seat the C-clip lock.

(3) I nsert the pinion gear mate shaft in the case.I nstall through the thrust washers and pinion gears.Align the hole in the shaft with the lock screw hole.I nstall the lock screw with L octite on the threads.Tighten the screw to 11 Nm (8 ft. lbs.) torque (Fig.1).

(4) Clean the cover and apply a bead of sealant.Refer to the Drain and Refill in this section.

(5) I nstall the brake drum. I nstall the wheel andtire.

(6) Raise or lower the hoist until the vehicle islevel.

(7) Remove the fill hole plug. Fill the differentialhousing with lubricant. Refer to the Specificationschart for the type and the quantity. Install the fillhole plug.

(8) L ower the vehicle and test the brakes and axlefor correct operati on.

PINIONSEAL REPLACEMENT

CAUTION: The following procedures must be usedso the correct pinion bearing preload torque is re-tained. If this procedure is not completely followed,the result can be premature failure of the rear axle.

REMOVAL

(1) Raise and support the vehicle.(2) Mark the U-joint, pinion yoke, and pinion shaft

for reference.(3) Di sconnect the drive shaft from the pinion

yoke. Secure the drive shaft in an upright position toprevent damage to the rear U-joint.

(4) Remove the rear wheels and tire and brakedrums to prevent any drag. The drag can cause apossible false bearing preload torque measurement.

(5) Use a Newton-meter or an inch-pound torquewrench to measure the pinion bearing preload. Ro-tate the pinion shaft several times with the torquewrench. Note the indicated torque as the wrench ismoved through several revolutions.

This measurement is important because bear-ing preload torque must be carefully re-ad-justed after the seal installation.

(6) Remove the pinion gear nut and washer. UsePuller C-452 and Wrench C-3281 to remove the pin-

ion gear yoke (F ig. 8).

(7) L ower the rear of the vehicle to prevent lubri-cant l eakage.

(8) Remove the pinion shaft seal with Puller C-748(Fig. 9). Cl ean the seal contact surface in the housingbore.

INSTALLATION

(1) Examine the splines on the pinion shaft forburrs or wear.

(2) Remove any burrs and clean the shaft.(3) I nspect the pinion yoke for cracks, worn splines

and a worn seal contact surface. Repair or replacethe yoke as necessary.

The outer perimeter of the seal is pre-coatedwith a special sealant. An additional applica-tion of sealant is not required.

(4) I nstall the new pinion shaft seal (Fig. 10) withSeal I nstaller C-4076-A and Handle C-4735.

The seal is correctly installed when the seal

Fig. 7 Axle Shaft Seal Installation

Fig. 8 Pinion Gear Yoke Removal



18/36

flange contacts the face of the differential hous-

ing flange.

(5) Position the pinion yoke on the end of the shaft

with the reference marks aligned.

(6) Seat the yoke on the pinion shaft with I nstallerC-3718 and Wrench C-3281.

(7) Remove the tools. I nstall the Belleville washer.

The convex side of the washer must face outward.

(8) Retain the pinion yoke with Wrench C-3281.

Tighten the shaft nut to 285 Nm (210 ft. lbs.) torque

(Fig. 11). Rotate the pinion shaft several complete

revolutions to ensure that the bearing rollers are

seated.

Use a Newton-meter or an inch-pound torque

wrench to measure the pinion gear bearing pre-

load torque.

CAUTION: Never loosen pinion gear nut to decrease

pinion gear bearing preload torque and never ex-

ceed specified preload torque. If preload torque is

exceeded a new collapsible spacer must be in-

stalled. The torque sequence will have to be re-

peated.

(9) Continue tightening and measuring the bearing

preload torque until the torque i s the same as the

original. The bearing preload torque should

never be greater than 1 N m (10 in. lbs.) more

than the recorded value.

The bearing preload torque should be con-

stant during a complete revolution of the pin-

ion gear. If preload torque varies, this indicates

a binding condition. This condition must be

corrected before the installation of the drive

shaft.

(10) I f the specified torque is not obtained, ti ghten

the nut in small increments until the preload torque

is obtained.

(11) The seal replacement is unacceptable if final

torque is less than 285 N m (210 ft. lbs.).

(12) I nstall the drive shaft with the installationreference marks aligned. Tighten the U-joint yoke

clamp screws to 19 Nm (14 ft. lbs./170 in. lbs.)

torque.

(13) I nstall the brake drums and wheels and tires.

(14) Adjust the hoist so that the vehicle is in a

level position and check the differential housing lu-

bricant level. If necessary, add a Mopar Hypoid Gear

L ubricant to increase the lubricant to the correct

level.

Fig. 9 Pinion Seal Removal

Fig. 10 Pinion Shaft Seal Installation

Fig. 11 Tightening Pinion Shaft Nut



19/36

DIFFERENTIAL SERVICE

SERVICE INFORMATION

I t is not necessary to remove the complete axle to

service the differential.

CAUTION: When differential service is necessary,

both rear wheels must be raised off the surface.They must be free to rotate.

CAUTION: Do not subject the bearings, cups, bores

or journals to heat from a torch or other abuse.

Otherwise permanent damage could result. Re-

moval and installation tools are recommended

when servicing a differential.

DIFFERENTIAL CASE REMOVAL

(1) Remove the axle shafts, refer to Axle Shaft Re-

moval.Side play and runout checks taken during

disassembly will be very useful in reassembly.

(2) Measure for differential side play. Position a

screwdriver or pinch bar between left side of axle

housing and case flange (Fig. 12). Use a prying mo-

tion to determine if any side play exists. There

should be no side play.

Side play from loose bearing races on case

hubs requires replacement of the differential

case. Otherwise, use threaded adjuster to re-

move the side play before measuring the ring

gear runout.

(3) Eliminate any side play in the differential case.

Attach Dial I ndicator to Pilot stud C-3288-B. Place

the indicator plunger at a right angle (90) to the

ring gear (Fig. 13). The plunger should exert a slight

force against the gear face.

(4) Measure the runout by turning the ring gear

several complete revolutions. Observe the dial i ndica-

tor pointer. M ark the ri ng gear and the differential

case at the areas of maximum runout. The ring gear

runout should not exceed 0.005 inch (0.13 mm). I f therunout exceeds 0.005 inch (0.13 mm), a damaged dif-

ferential case could be the cause.

The marking on the differential case will be

very useful later during the differential case

runout. Remove the rear wheel anti-lock

(RWAL ) sensor.

(5) Mark the differential housing and the differen-

tial bearing caps for installation r eference (Fig. 14).

(6) Remove the bearing threaded adjuster lock

from each bearing cap. L oosen the bolts, but do not

remove the bearing caps.

(7) L oosen the threaded adjusters with WrenchC-4164 (Fig. 15).

(8) Hold the differential case in place. Remove the

bearing caps (Fig. 16), adjusters (8 1/4 I nch axle

only) and the differential case.

Each differential bearing cup and threaded

adjuster must be kept with their respective

bearing. The adjusters for 7 1/4 I nch axles will

remain in the differential housing.

Fig. 12 Differential Case Side Play Test

Fig. 13 Ring Gear Runout Measurement



20/36

PINION GEAR SHAFT REMOVAL

(1) Remove the pinion gear nut and washer. Use

Puller C-452 and Wrench C-3281 to remove the pin-

ion gear yoke (F ig. 17).

(2) Remove the pinion shaft seal with Puller C-748

(Fig. 18). Clean the seal contact surface in the hous-

ing bore.

(3) Force the pinion gear out the front bearing to

remove the shaft and fr ont bearing. This will dam-

age the front bearing rollers and bearing cup.

The front bearing and cup must be replaced.

Discard the bearing collapsible spacer.

(4) Remove the front and r ear bearing cups with

Remover C-4306 and H andle C-4171.

Fig. 14 Housing & Caps Marked For InstallationReference

Fig. 15 Threaded Adjuster Tool

Fig. 16 Differential Bearing Cap Removed

Fig. 17 Pinion Gear Yoke Removal

Fig. 18 Pinion Seal Removal



21/36

(5) Remove the rear bearing from the pinion shaft

with Puller C-293-PA and Adapter (Fig. 19). Remove

and record the pini on gear depth shims.

7 1/4 I nch axle use Adapter C-293-40

8 1/4 I nch axle use Adapter C-293-42

RING GEAR

Do not remove the ring gear from case unless

the runout must be measured.

(1) Clamp the case (with the ring gear bolts facing

upward). Use a vise equipped with soft jaws (brass).(2) Remove and discard the ring gear bolts. The

bolts have left-hand threads. Use a hammer and a

brass drift to force the ring gear loose from the case

pilots. Remove the ring gear.

CASE FLANGE RUNOUT MEASUREMENT

(1) I f the ring gear runout exceeded 0.005 inch

(0.13 mm), case flange runout should also be mea-

sured. I nstall the case with the bearing cups and the

threaded adjusters close to their original position.

(2) I nstall the bearing caps and bolts. Tighten the

bolts lightly. Use Wrench C-4164 to thread both ad-justers inward. Remove all side play.

(3) Attach Dial I ndicator to measure the flange

runout. The plunger should contact the ring squarely

between the outer edge and the gear bolt holes (Fig.

20).

(4) Rotate the differential case several times. Ob-

serve the dial indicator pointer. Mark the area of

maximum flange runout. The differential case flange

runout must not exceed 0.003 inch (0.08 mm). I f the

runout exceeds the amount, replace the differential

case.

To reduce ring gear runout, positioning the

ring gear r unout mark 180 degrees opposite the

flange runout mark.(5) Remove the differential bearing cap bolts. Re-

move the differential case from the differential hous-

ing.

DIFFERENTIAL CASE DISASSEMBLY

(1) Rotate the side gears until the pinion gears are

located at the differential case opening and remove

them.

(2) Remove the side gears and the thrust washers.

(3) Remove the differential bearings from the case

hubs with Puller C-293-PA, Adapter and Plug

SP-3289 (Fig. 21).

7 1/4 I nch axle use Adapter C-293-44 8 1/4 I nch axle use Adapter C-293-48

CLEANING AND INSPECTION

(1) Cl ean all of the differential components incleaning solvent. Allow the bearings to either air dryor dry them with a li nt-free cloth. Dry the other com-ponents with compressed air.

(2) Examine each component for wear or damage.(3) Replace shims, bearings and cups as a set only.

Replace bearings and cups i f either is galled, worn,cracked, or damaged.

(4) I nspect the differential side and pinion gears.

Replace any gear that is worn, cracked or chipped.(5) I nspect the differential case. Replace the case if

cracked or damaged.Polish each axle shaft with No. 600 crocus

cloth. This can remove slight surface damage.Do not reduce the diameter of the axle shaftseal contact surface. When polishing, the crocuscloth should be moved around the circumfer-ence of the shaft (not in-line with the shaft).

When replacing a drive pinion gear bearing,always replace the bearing and cup as amatched set only.

Fig. 19 Inner Bearing Removal

Fig. 20 Case Flange Runout Measurement



22/36

(6) I nspect the axle shaft C-clip locks for cracks

and excessive wear. Replace them if necessary.

(7) Test each threaded adjuster to determine i f it

rotates freely.(8) If an adjuster binds, repair the damaged

threads or replace the adjuster.

EXCITER RING REPLACEMENT

The ring gear must be removed before the RWAL

brake exciter ring can be replaced.

(1) Remove exciter ring with a hammer and drift.

(2) Heat the replacement exciter ring with a heat

lamp or by immersing in a hot fluid. The tempera-

ture should not exceed 149C (300F). Do not use a

torch to heat the ring.

(3) After heating, quickly position the exciter ring

on the differential case adjacent to the flange.

DIFFERENTIAL CASE ASSEMBLY

(1) L ubricate all the differential case components

with gear l ubricant.

(2) Place the thrust washers on the differential

side gears. P osition the gears i n the differential case

counterbores.

If replacement side gears or thrust washers

are used, refer to Differential Side Gear Clear-

ance Measurement And Adjustment.

(3) Position the thrust washers on the differential

pinion gears. Mesh the pinion gears with the sidegears. Ensure that the pinion gears are exactly180 degrees opposite each other.

(4) Rotate the side gears to ali gn the pinion gearsand thrust washers. Align these components with themate shaft bores i n the case.

(5) I f the ring gear was removed, clean all contactsurfaces. Use an Arkansas stone or fine file to re-move any sharp areas from the chamfered inside di-ameter.

(6) I f removed, heat ring gear with a heat lamp orby immersing in a hot fluid. The temperature shouldnot exceed 149C (300F). Do not use a torch toheat the ring.

(7) Position heated gear on case. Use two equallyspaced Pi lot Studs C-3288-B to align the gear withthe flange holes (Fig. 22).

(8) I nstall replacement ring gear bolts (with lefthand threads). Tighten bolts to 95 Nm (70 ft. lbs.)torque.

CAUTION: When installing a differential bearing,never apply force to the bearing cage because bear-ing damage will result.

(9) Pl ace a differential bearing on each hub (F ig.23).

7 1/4 I nch axle, use I nstaller C-3716-A and H andleC-4171 8 1/4 I nch axle, use I nstaller C-4340 and HandleC-4171

PINIONDEPTH MEASUREMENT AND ADJUSTMENT

WITHGAUGE SET(1) Use pinion gear adjustment gauge set C-3715-B

(Fig. 24, 25) and continue the assembly:(2) I nstall front (outer) bearing cup use Installer

D-130 and Handle C-4171.(3) I nstall rear (inner) bearing cup.

Fig. 21 Differential Bearing Removal

Fig. 22 Case-To-Ring Gear Alignment



23/36

8 1/4 I nch axles, use Installer C-4308 and HandleC-4171 7 1/4 I nch axles, use I nstaller D-146 and HandleC-4171

7 1/4 Inch axles assemble tools as described(Fig. 24);

Position Spacer (SP-3244) over Shaft (SP-5385) Position pinion rear bearing on shaft Position tools (with bearing) in the housing I nstall Sleeve (SP-3245) I nstall pinion front bearing I nstall Sleeve (SP-3194-B), Washer (SP-534) andNut (SP-3193).

8 1/4 Inch axles assemble tools as described(Fig. 25); Position Spacer (SP-6030) over Shaft (SP-5385) Position pinion rear bearing on shaft Position tools (with bearing) in the housing

I nstall Sleeve (SP-5382)

I nstall pinion front bearing

I nstall Spacer (SP-6022)

I nstall Sleeve (SP-3194-B), Washer (SP-534) and

Nut (SP-3193).

(4) Pr event compression sleeve tool from turningwith Wrench C-3281. Tighten the nut to seat the pin-ion bearings in the housing (Fi g. 26). Allow thesleeve to turn several times during the ti ghtening toprevent brinelli ng the bearing cups or the bearings.

Shim(s) positioned between the pinion gearand rear bearing provide the corrected piniondepth. The required thickness of the depthshim(s) is determined with the following i nfor-mation.

(5) L oosen the compression nut tool. L ubricate thepinion gear front and rear bearings with gear lubri-cant. Re-tighten the compression nut tool to 1 to 3Nm (15 to 25 in. lbs.) torque. Rotate the pinion gearseveral complete revolutions to align the bearing roll-ers.

(6) I nstall Gauge Block.

Fig. 23 Differential Bearing Installation

Fig. 24 7 1/4 Inch Axle Pinion Adjustment Tools

Fig. 25 8 1/4 Inch Axle Pinion Adjustment Tools

Fig. 26 Seating Pinion Bearings



24/36

7 1/4 Inch axles (Fig. 24)

I nstall Gauge Block SP-3250 at the end of SP -5385

I nstall Cap Screw (SP-536) and tighten with

Wrench SP-531

8 1/4 Inch axles (Fig. 25)

I nstall Gauge Block SP-5383 at the end of SP -5385

I nstall Cap Screw (SP-536) and tighten with

Wrench SP-531(7) Position Crossbore Arbor in the differential

housing.

7 1/4 I nch axles (F ig. 24); (SP-3243)

8 1/4 I nch axles (F ig. 25); (SP-6029)

(8) Center the tool. Place a piece of 0.002 inch

shim stock at each end of the arbor. Position the

bearing caps on the arbor tool. I nstall the bolts.

Tighten the cap bolts to 14 Nm (10 ft. lbs.) torque.

(9) Trial fit depth shim(s) between the crossbore

arbor and gauge block (Fig. 27). The depth shim(s)

fit must be snug but not tight (drag friction of a

feeler gauge blade).Depth shims are available in 0.001-inch incre-

ments from 0.020 inch to 0.038 inch.

(10) Note the etched number on the face of the

drive pinion gear. The numbers represent thousands-

of-an-inch deviation from the standard. I f the num-

ber is - (negative), add that value to the r equired

thickness of the depth shim(s). I f the number is +

(positive), subtract that value from the thickness of

the depth shim(s). I f the number is 0, no change is

necessary.

(11) Remove the tools from the differential hous-

ing.

(12) Position the depth shim(s) on the pinion gear.

Install the rear bearing (Fig. 28). Be sure the contact

surfaces are clean and without foreign particles. 7 1/4 I nch axles use Installer C-3717

8 1/4 I nch axles use Installer C-4040

(13) L ubricate the pinion gear front and rear bear-

ings with gear lubricant.

(14) I nstall the pinion gear in the housing. I nstall

the new collapsible spacer at the end of the pinion

gear. I nstall the pinion gear front bearing.

(15) I nstall the pinion yoke with Remover/I nstaller

C-3718 and Wrench C-3281 (Fig. 27).

It is necessary to use the tools (above) to cor-

rectly seat the front bearing on the drive pin-

ion gear shaft (Fig. 29).

Fig. 27 Depth Shim(s) Selection

PINION GEAR DEPTH VARIANCE



25/36

CAUTION: Use care to prevent collapsing preload

collapsible spacer during installation of the yokeand seating the front bearing.

(16) Remove yoke and tools from the pinion gear.

(17) I nstall the pinion seal with Seal I nstaller

C-4076-A and Handle C-4735 (Fig. 30).

The outer perimeter of the seal is pre-coated

with a special sealant. An additional applica-

tion of sealant is not required.

(18) I nstall the pinion yoke with Remover/Installer

C-3718 and Wrench C-3281.

(19) Remove the tools. I nstall the Belleville

washer. T he convex side of the washer must face out-

ward. I nstall the pinion nut.(20) Retain pinion yoke with Wrench C-3281. I ni-

tially tighten the drive pinion gear shaft nut enough

to remove the bearing end play. While tightening, ro-

tate the pinion shaft to ensure the bearing rollers are

correctly seated.

(21) Tighten the pinion nut to (F ig. 31) 285 Nm

(210 ft. lbs.) torque (minimum).

(22) Remove the tools from the shaft. Rotate the

pinion several complete revoluti ons (both directions)

to seat the bearing rollers.

Fig. 28 Shaft Rear Bearing Installation

Fig. 29 Pinion Yoke Installation

Fig. 30 Pinion Gear Seal Installation

Fig. 31 Tightening Pinion Gear Nut



26/36

CAUTION: Never loosen the pinion gear nut to de-

crease the pinion gear bearing preload torque. If the

specified preload torque is exceeded, a replacement

collapsible spacer must be installed. The torque se-

quence will have to be repeated.

(23) Measure the pinion bearing preload torque by

rotating pinion shaft with a Newton-meter or aninch-pound torque wrench. The correct bearing pre-

load torque is 1 to 2 N m (10 to 20 in. lbs.). This

torque value is with replacement bearings and pinion

nut tightened to a minimum of 285 N m (210 ft. lbs.)torque (Fig. 32).

When using original pinion rear bearing anda replacement front bearing. The correct pre-load torque is 1 Nm (10 in. lbs.) plus the torquemeasured during disassembly.

Bearing preload torque should be constantduring rotation of the drive pinion gear shaft.If preload torque varies during shaft rotation,an internal binding must be corrected before fi-nal assembly.

(24) I f the specifi ed torque is not obtained, tightenthe nut in small increments until the preload torqueis obtained.

The differential will be unacceptable for useif the final nut torque is less than 285 Nm (210ft. lbs.) torque. If the preload torque is notwithin the specified range this is also unaccept-able.

DIFFERENTIAL CASE INSTALLATION

(1) Apply a coating of hypoid gear lubricant to thedifferential bearings, bearing cups and threaded ad-justers. A dab of grease can be used to keep the ad-justers in position. Carefully position the assembleddifferential case in the housing.

(2) Observe the reference marks and install thedifferential bearing caps at their original locations(Fig. 33).

(3) I nstall the bearing cap bolts (Fig. 33). Tighten

the upper bolts to 14 Nm (10 ft. lbs.) torque.

Tighten the lower bolts finger-tight until the bolthead is lightly seated.

DIFFERENTIAL BEARING PRELOAD AND RING

GEAR BACKLASH ADJUSTMENT

The following limitations must be considered when

adjusting the preload torque and backlash:

The maximum ring gear backlash variation is

0.003 i nch (0.076 mm)

Mark the gears so the same teeth are meshed dur-ing all backlash measurements Maintain the specified threaded-adjuster torquewhile adjusting the preload torque and backlash

Excessive adjuster torque will introduce a highbearing load and cause premature bearing failure; in-sufficient adjuster torque can result in excessive dif-ferential case free-play and ring gear noise I nsufficient adjuster torque can cause excessivedifferential case free-play and ring gear noise

The differential bearing cups will not alwaysimmediately follow the threaded adjusters asthey are moved during adjustment. Ensure ac-curate bearing cup responses to the adjust-ments. Maintain the gear teeth engaged(meshed) as marked. The bearings must beseated by rapidly rotating the pinion gear a

half turn back and forth. Do this five to tentimes each time the threaded adjusters are ad-justed.

(1) Use Wrench C-4164 to adjust each threaded ad-juster inward (Fig. 34) until the differential bearingfree-play is eliminated. Allow some ri ng gear back-lash (approximately 0.01 inch/0.25 mm) between thering and pinion gear. Seat the bearing cups with theprocedure described above.

(2) I nstall Dial I ndicator (Fig. 35). Position theplunger against the drive side of a ring gear tooth.Measure the backlash at 4 positions (90 degrees

Fig. 32 Bearing Preload Torque Measurement

Fig. 33 Bearing Caps & Bolts



27/36

apart) around the r ing gear. L ocate and mark the

area of minimum backlash.

(3) Rotate the ring gear to the position of the least

backlash. M ark the gear so that all future backlash

measurements will be taken with the same gear

teeth meshed.

(4) L oosen the right-side, tighten the left-side

threaded adjuster. Obtain backlash of 0.003 to 0.004

inch (0.076 to 0.102 mm) with each adjuster tight-

ened to 14 Nm (10 ft. lbs.) torque. Seat the bearing

cups with the procedure descri bed above.(5) Tighten the differential bearing cap bolts;

7 1/4 Inch axles to 61 N m (45 ft. lbs.) torque 8 1/4 Inch axles to 95 N m (70 ft. lbs.) torque

(6) Use Wrench C-4164 to tighten the right-sidethreaded adjuster to 95 Nm (70 ft. lbs.) torque. Seatthe bearing cups with the procedure described above.Continue to tighten the right-side adjuster and seatbearing cups until the torque remains constant at 95Nm (70 ft. lbs.)

(7) Measure the ring gear backlash. The range ofbacklash is;

7 1/4 I nch axles, 0.003 to 0.006 inch (0.076 to

0.152 mm)

8 1/4 I nch axles, 0.005 to 0.008 inch (0.127 to

0.203 mm)

Continue increasing the torque at the right-side

threaded adjuster until the specifi ed backlash is ob-

tained.

The left-side threaded adjuster should haveapproximately 95 Nm (70 ft. lbs.) torque. If the

torque is considerably less, the complete ad-

justment procedure must be repeated.

(8) Tighten the left-side threaded adjuster until 95

Nm (70 ft. lbs.) torque is indicated. Seat the bearing

rollers with the procedure described above. Do this

until the torque remains constant.

(9) Install the threaded adjuster locks . Ensure the

lock finger is engaged with the adjuster hole. Ti ghten

the lock screws to 10 Nm (90 in. lbs.) torque.

SIDE GEAR CLEARANCE MEASUREMENT AND

ADJUSTMENT

When measuring side gear clearance, check each

gear independently. One side gear can have an ac-

ceptable clearance and other side gear an unaccept-

able clearance. I f it necessary to replace a side gear,

replace both gears as a matched set.

(1) I nstall the axle shafts and C-clip locks and pin-

ion mate shaft. I f necessary, refer to the i nstallation

located within this group.

(2) Measure each side gear clearance. I nsert a

matched pair of feeler gauge blades between the gear

and differential housing on opposite sides of the hub

(Fig. 36).

(3) I f side gear clearances is no more than 0.005

inch. Determine if the shaft is contacting the pinion

gear mate shaft. Do not remove the feeler

gauges. Inspect the axle shaft with the feeler

gauge inserted behind the side gear. I f the end of

Fig. 34 Threaded Adjuster Tool

Fig. 35 Ring Gear Backlash Measurement

Fig. 36 Side Gear Clearance Measurement



28/36

the axle shaft is not contacting the pinion gear mate

shaft, the side gear clearance is acceptable.

(4) I f clearance is more than 0.005 inch (axle shaft

not contacting mate shaft), record the side gear clear-

ance. Remove the thrust washer and measure its

thickness with a micrometer. Add the washer thick-

ness to the recorded side gear clearance. The sum of

gear clearance and washer thickness will determinerequired thickness of replacement thrust washer

(Fig. 37).

I n some cases, the end of the axle shaft will move

and contact the mate shaft when the feeler gauge is

inserted. The C-clip lock is preventing the side gear

from sliding on the axle shaft.

(5) I f there is no side gear clearance, remove the

C-clip lock from the axle shaft. Use a micrometer to

measure the thrust washer thickness. Record the

thickness and re-install the thr ust washer. Assemble

the differential case without the C-clip lock installed

and re-measure the side gear clearance.

(6) Compare both clearance measurements. I f thedifference is less than 0.012 inch (0.305 mm), addclearance recorded when the C-clip lock was installed

to thrust washer thickness measured. The sum willdetermine the required thickness of the replacementthrust washer.

(7) I f clearance is 0.012 inch (0.305 mm) or greater,

both side gears must be replaced (matched set) and

the clearance measurements repeated.

(8) I f clearance (above) continues to be 0.012 i nch

(0.305 mm) or greater, the case must be replaced.

RING GEAR TEETH CONTACT PATTERN

ANALYSISThe ring gear teeth contact patterns will show if

the pinion gear depth shim(s) have the correct thick-

ness. I t will also show if the ring gear backlash has

been adjusted correctly. The backlash must be main-

tained within the specified limits until the correct

teeth contact patterns are obtained.

Excessive backlash is corrected by moving the ring

gear teeth closer to the pinion gear teeth

I nsufficient backlash is corrected by moving the

ring gear away from the pinion gear

(1) Apply yellow ferrous (iron) oxide compound to

both drive and coast sides of ring gear teeth.

(2) Rotate the ring gear one complete revolution in

both directions.

(3) Note patterns in compound. Refer to (Fig. 38)

for interpretation of contact patterns and adjust as

necessary.

(4) I nstall the axle shafts. Refer to Axle Shaft I n-

stallation within this group.

(5) I nstall the housing cover. Refill the differential

with lubricant. Refer to Axle Shaft I nstallation.

(6) I nstall the RWAL brake speed sensor and cover

onto the axle housing. Tighten the sensor to 24 Nm

(18 ft. lbs.) torque.

Fig. 37 Side Gear Calculations



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Fig. 38 Gear Teeth Contact Patterns



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TRAC-LOC DIFFERENTIAL

GENERAL INFORMATIONThe Trac-Loc differential is an option available in

the 8 1/4 I nch rear axles (Fi g. 1).I n a conventional differential, the torque applied to

the ring gear is transmitted to the axle shafts

through 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.

I n 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.

I n operation, the Trac-L ok clutches are engaged bytwo concurrent forces. The first being preload force

exerted through Belleville spring washers. The sec-ond is from separating forces generated by the sidegears (Fig. 1).

The Trac-Lok design provides the normal differen-tial action needed for turning corners. I t also pro-vides for the transmission of equal torque to bothwheels when driving straight ahead. When one wheelloses traction, the clutch packs transfer torque to thewheel having the most traction. Trac-Lok differen-tials resist wheel spin on bumpy roads. I t also pro-vides more pulling power when one wheel losestraction. Pulling power is continuous until bothwheels lose traction. If both wheels slip due to un-

equal traction, Tr ac-Lok operation is normal. I n ex-treme cases of differences of traction, the wheel withthe l east traction may spin. This occurs after theTrac-Lok has transferred as much torque as possibleto the non-spinning wheel.

NOISE DIAGNOSISI f chatter 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 L ubricant change in this Group.

A container of Trac-Lok L ubricant (friction modi-fier) should be added after.

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.

Refer to Group 0, L ubrication and M aintenance foradditional information.

DIFFERENTIAL TEST

WARNING: WHEN SERVICING VEHICLES WITH A

LIMITED 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 IN

CONTACT WITH THE SURFACE) TO CAUSE THE

VEHICLE TO MOVE.

The differential can be tested without removing the

differential case by measuring rotating torque. Make

sure brakes are not dragging during this measure-

ment.

(1) Engine off, transmission in neutral, and park-

ing brake off.

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

(3) J ack up one rear wheel until it is completely off

the ground.

(4) Remove wheel and bolt special tool to studs.

(5) Use torque wrench on Special Tool 6790 to ro-

tate wheel and r ead rotating torque (Fi g. 2).

(6) I f rotating torque is less than 22 Nm (30 ft.

lbs.) or more than 271 Nm (200 ft. lbs.) on either

wheel the uni t should be service.

Fig. 1 Limited Slip Differential OperationBothWheels Driving



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DIFFERENTIAL OVERHAULThe Trac-Lok differential components are ill us-

trated in (Fig. 3). Refer to this illustration during re-

pair service.

DISASSEMBLY

Service to the Trac-Lok differential requires theuse of Tool Set C-4487 (J -23781). Refer to Axle sec-tion in this Group for Differential Removal and I n-stallation.

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

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

(3) Remove and discard the ring gear bolts. Tap

the ring gear with a rawhide or plastic mallet and re-

move (Fig. 6).

(4) Remove the pinion gear mate shaft lock screw

(Fig. 7).

(5) Remove the pinion gear mate shaft with a drift

and hammer (Fi g. 8).

(6) I nstall and lubricate Step Plate C-4487-1 (Fig.

9).

(7) Assemble Threaded Adapter C-4487-3 into top

side gear. Thread forcing Screw C-4487-2 into

adapter until it becomes centered in adapter plate.

Fig. 3 Trac-Lok Differential Components

Fig. 2 Trac-Loc Test

Fig. 4 Axle Shaft As Holding Fixture



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(8) Position a small screw driver in slot of

Threaded Adapter C-4487-3 (Fig. 10 to prevent

adapter from turning.

(9) T ighten forcing screw tool enough to relieve

clutch pack tension. Remove both pinion thrust

washers (Fig. 11).(10) L oosen the forcing screw tool until the clutch

pack tension is relieved.(11) I nsert Turning Bar C-4487-4 in case. Rotate

case with tool until pinion gears can be removed (Fig.12).

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

(13) Remove case from fixture. Remove r emainingclutch pack.

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

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



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CLEANING AND INSPECTION

(1) Clean all components in cleaning solvent. Drycomponents with compressed air.

(2) I nspect clutch pack plates for wear, scoring or

damage. Replace both clutch packs if any one compo-

nent in either pack is damaged.

(3) I nspect side and pinion gears. Replace any gear

that is worn, cracked, chipped or damaged.

(4) I nspect differential case and pinion shaft. Re-

place i f worn or damaged.

PRESOAK PLATES AND DISC

Pl ates and discs with fiber coating (no groves or

lines) must be presoaked in Friction Modifier before

assembly. Soak plates and discs for a minimum of 20

minutes before assembly. Add remaining Friction

Modifier to differential after assembly.

ASSEMBLY

(1) The clutch discs are replaceable as complete

sets only. If one clutch disc pack is damaged, both

Fig. 10 Threaded Adapter Installation

Fig. 11 Remove Pinion Thrust Washer

Fig. 12 Pinion Gear Removal

Fig. 13 Side Gear & Clutch Disc Removal



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packs must be replaced. L ubricate each component

with gear lubricant before assembly and installation.

(2) Assemble the clutch discs into packs and secure

disc packs with retaining clips (Fig. 14).

(3) Position assembled clutch disc packs on the

side gear hubs.

(4) Position case on axle fixture.

(5) I nstall clutch pack and side gear in lower bore

(Fig. 15). Be sure clutch pack retaining clips remain

in position and are seated in the case pockets.

(6) I nstall lubricated Step Pl ate C-4487-1 on first

clutch pack (Fi g. 16).

(7) I nstall the upper side gear and clutch disc pack

(Fig. 16).

(8) H old assembly in position. I nsert ThreadedAdapter C-4487-3 into top side gear, insert forcingScrew C-4487-2.

(9) Tighten forcing screw tool to compress clutchdiscs.

(10) I nstall pinion gears. Rotate case with TurningBar C-4487-4. M ake sure holes of pinion mate gearsare aligned with case.

(11) Tighten forcing screw to compress theBelleville plates. L ubricate and install pinion gearthrust washers with a small screw driver.

(12) I nstall pinion gear mate shaft ( align holes inshaft and case).

(13) I nstall the pinion mate shaft lock screw fingertight.

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.

Fig. 14 Clutch Disc Pack

Fig. 15 Clutch Discs & Lower Side Gear Installation

Fig. 16 Upper Side Gear & Clutch Disc PackInstallation



35/36

(14) I nvert the differential case and start two ring

gear bolts. This will provide case-to-ring gear bolt

hole alignment.

(15) I nstall new ring gear bolts and alternately

tighten to 95-122 Nm (70-90 ft. lbs.) torque (Fig. 17).

(16) L ubricate all differential components with hy-

poid gear lubricant.

Fig. 17 Ring Gear Bolt Installation



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AXLE SPECIFICATIONS

7 1/4 INCH AXLEAxle Type................................Semi-floating, hypoid

Lubricant...............................................SAE 80W-90

Lube Capacity...................................1.4 L (3.0 pts)

Axle Ratio............................................................3.55

DifferentialCase Clearance...........................0.30 mm (0.012 in.)

Case F lange Runout ................0.076 mm (0.003 in.)

Ring Gear

Diameter .......................................18.41 cm (7.25 i n.)

Backlash....................0.07-0.15 mm (0.003-0.006 in.)

Runout.......................................0.127 mm (0.005 in.)

Pinion Bearing

Preload....................................1-2 Nm (10-20 in.lbs.)

8 1/4 INCH AXLEAxle Type................................Semi-floating, hypoidLubricant...............................................SAE 80W-90Lube Capacity..................................2.1 L (4.4 pts.)Trac-Loc Additive..............................118 ml (4 oz.)

Axle Ratio.........................................3.21, 3.55, 3.90DifferentialCase Clearance...........................0.12 mm (0.005 in.)Case F lange Runout ................0.076 mm (0.003 i n.)Ring GearDiameter .......................................20.95 cm (8.25 i n.)Backlash....................0.12-0.20 mm (0.005-0.008 in.)Runout .......................................0.127 mm (0.005 in.)Pinion BearingPreload....................................1-2 Nm (10-20 in.lbs.)

TORQUE SPECIFICATIONS

SUSPENSIONCOMPONENTS

DESCRIPTION................................................TORQUE

Shock AbsorberL ower Bolt ...................................88 Nm (65 ft. lbs.)Upper Bolt ...................................27 Nm (20 ft. lbs.)Spring Clamp Nut2WD..............................................88 Nm (65 ft. lbs.)4WD ..........................................149 Nm (110 ft. lbs.)

SpringSpring E ye Nut ...........................88 Nm (65 ft. lbs.)Pivot Bolt Nut .............................88 N m (65 ft. lbs.)

7 1/4 and 8 1/4 AXLES

DESCRIPTION................................................TORQUE

Diff. Cover Bolt ........................47 Nm (35 ft. lbs.)

Bearing Cap Bolt

7 1/4 Axle.....................................61 N m (45 ft. lbs.)

8 1/4 Axle.....................................95 N m (70 ft. lbs.)

Pinion Nut .............................285 Nm (210 ft. lbs.)

Ring Gear Bolt .........................95 Nm (70 ft. lbs.)

RWAL/ABS Sensor Bolt .........24 Nm (18. ft. lbs.)


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