2003 Dodge RAM Standard Owners Manual

driving the vehicle at least 5 miles and then acceler- ate the vehicle to the speed range where the noise is the greatest. Shift out-of-gear and coast through the peak-noise range. If the noise stops or changes greatly:

† Check for insufficient lubricant. † Incorrect ring gear backlash. † Gear damage. Differential side gears and pinions can be checked by turning the vehicle. They usually do not cause noise during straight-ahead driving when the gears are unloaded. The side gears are loaded during vehi- cle turns. A worn pinion mate shaft can also cause a snapping or a knocking noise.

BEARING NOISE

The axle shaft, differential and pinion bearings can all produce noise when worn or damaged. Bearing noise can be either a whining, or a growling sound. Pinion bearings have a constant-pitch noise. This noise changes only with vehicle speed. Pinion bearing noise will be higher pitched because it rotates at a faster rate. Drive the vehicle and load the differen- tial. If bearing noise occurs, the rear pinion bearing is the source of the noise. If the bearing noise is

FRONT AXLE - 9 1/4 AA

3 - 46
FRONT AXLE - 9 1/4 AA (Continued)

heard during a coast, the front pinion bearing is the source.

Worn or damaged differential bearings usually pro- duce a low pitch noise. Differential bearing noise is similar to pinion bearing noise. The pitch of differen- tial bearing noise is also constant and varies only with vehicle speed.

Axle shaft bearings produce noise and vibration when worn or damaged. The noise generally changes when 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 noise level. Where axle bearing damage is slight, the noise is usually not noticeable at speeds above 30 mph.

LOW SPEED KNOCK

Low speed knock is generally caused by a worn U-joint or by worn side-gear thrust washers. A worn pinion shaft bore will also cause low speed knock.

VIBRATION

caused by:

Vibration at the front/rear of the vehicle is usually † Damaged drive shaft. † Missing drive shaft balance weight(s). † Worn or out of balance wheels. † Loose wheel lug nuts. † Worn U-joint(s).

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† Loose/broken springs. † Damaged axle shaft bearing(s). † Loose pinion gear nut. † Excessive pinion yoke run out. † Bent axle shaft(s). Check for loose or damaged front end components or engine/transmission mounts. These components can contribute to what appears to be a vibration. Do not overlook engine accessories, brackets and drive belts.

DRIVELINE SNAP

into gear (or the clutch engaged) can be caused by:

A snap or clunk noise when the vehicle is shifted † High engine idle speed. † Transmission shift operation. † Loose engine/transmission/transfer case mounts. † Worn U-joints. † Loose spring mounts. † Loose pinion gear nut and yoke. † Excessive ring gear backlash. † Excessive 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 vehi- cle on a hoist with the wheels free to rotate. Instruct the helper to shift the transmission into gear. Listen for the noise, a mechanics stethoscope is helpful in isolating the source of a noise.

DIAGNOSTIC CHART

Condition

Possible Causes

Correction

Wheel Noise

1. Wheel loose.

1. Tighten loose nuts.

2. Faulty, brinelled wheel bearing.

2. Replace bearing.

Axle Shaft Noise

1. Misaligned axle tube.

2. Bent or sprung axle shaft. 3. End-play in pinion bearings.

4. Excessive gear backlash between the ring gear and pinion.

5. Improper adjustment of pinion gear bearings. 6. Loose pinion yoke nut. 7. Scuffed gear tooth contact surfaces.

1. Inspect axle tube alignment. Correct as necessary.

2. Inspect and correct as necessary. 3. Refer to pinion pre-load information and correct as necessary. 4. Check adjustment of the ring gear and pinion backlash. Correct as necessary. 5. Adjust the pinion bearings pre-load. 6. Tighten the pinion yoke nut. 7. Inspect and replace as necessary.

DR FRONT AXLE - 9 1/4 AA (Continued)

FRONT AXLE - 9 1/4 AA

3 - 47

Condition

Possible Causes

Correction

Axle Shaft Broke

1. Misaligned axle tube.

2 Vehicle overloaded.

3. Erratic clutch operation.

4. Grabbing clutch.

Differential Cracked

1. Improper adjustment of the differential bearings.

2. Excessive ring gear backlash.

3. Vehicle overloaded.

4. Erratic clutch operation.

Differential Gears Scored

1. Insufficient lubrication.

2. Improper grade of lubricant.

3. Excessive spinning of one wheel/tire.

Loss Of Lubricant

1. Lubricant level too high.

2. Worn axle shaft seals. 3. Cracked differential housing. 4. Worn pinion seal. 5. Worn/scored yoke. 6. Axle cover not properly sealed.

1. Replace the broken shaft after correcting tube mis-alignment.

2. Replace broken shaft and avoid excessive weight on vehicle. 3. Replace broken shaft and avoid or correct erratic clutch operation. 4. Replace broken shaft and inspect and repair clutch as necessary.

1. Replace case and inspect gears and bearings for further damage. Set differential bearing pre-load properly.

2. Replace case and inspect gears and bearings for further damage. Set ring gear backlash properly. 3. Replace case and inspect gears and bearings for further damage. Avoid excessive vehicle weight. 4. Replace case and inspect gears and bearings for further damage. Avoid erratic use of clutch.

1. Replace scored gears. Fill differential with the correct fluid type and quantity.

2. Replace scored gears. Fill differential with the correct fluid type and quantity. 3. Replace scored gears. Inspect all gears, pinion bores, and shaft for damage. Service as necessary.

1. Drain lubricant to the correct level.

2. Replace seals. 3. Repair as necessary. 4. Replace seal. 5. Replace yoke and seal. 6. Remove, clean, and re-seal cover.

Axle Overheating

1. Lubricant level low.

1. Fill differential to correct level.

2. Improper grade of lubricant.

3. Bearing pre-loads too high. 4. Insufficient ring gear backlash.

2. Fill differential with the correct fluid type and quantity. 3. Re-adjust bearing pre-loads. 4. Re-adjust ring gear backlash.

FRONT AXLE - 9 1/4 AA

3 - 48
FRONT AXLE - 9 1/4 AA (Continued)

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Condition

Possible Causes

Correction

Gear Teeth Broke

1. Overloading.

2. Erratic clutch operation.

3. Ice-spotted pavement.

4. Improper adjustments.

Axle Noise

1. Insufficient lubricant.

2. Improper ring gear and pinion adjustment. 3. Unmatched ring gear and pinion.

4. Worn teeth on ring gear and/or pinion. 5. Loose pinion bearings. 6. Loose differential bearings.

7. Mis-aligned or sprung ring gear.

8. Loose differential bearing cap bolts.

9. Housing not machined properly.

1. Replace gears. Examine other gears and bearings for possible damage.

2. Replace gears and examine the remaining parts for damage. Avoid erratic clutch operation. 3. Replace gears and examine remaining parts for damage. 4. Replace gears and examine remaining parts for damage. Ensure ring gear backlash is correct.

1. Fill differential with the correct fluid type and quantity. 2. Check ring gear and pinion contact pattern. 3. Replace gears with a matched ring gear and pinion. 4. Replace ring gear and pinion.

5. Adjust pinion bearing pre-load. 6. Adjust differential bearing pre-load. 7. Measure ring gear run-out. Replace components as necessary. 8. Inspect differential components and replace as necessary. Ensure that the bearing caps are torqued tot he proper specification. 9. Replace housing.

REMOVAL

(1) Remove wheels and tires. (2) Remove brake calipers and rotors. (3) Disconnect ABS wheel speed sensors. (4) Disconnect axle vent hose. (5) Remove front propeller shaft. (6) Disconnect stabilizer bar links at

the axle

brackets.

ing knuckles.

assembly.

(7) Disconnect shock absorbers from axle brackets. (8) Disconnect track bar from the axle bracket. (9) Disconnect tie rod and drag link from the steer-

(10) Position suitable lifting device under the axle

(11) Secure axle to lifting device. (12) Mark suspension alignment cams for installa-

tion reference.

from the axle bracket.

(13) Disconnect upper and lower suspension arms

(14) Lower the axle. The coil springs will drop

with the axle.

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

INSTALLATION

CAUTION: Suspension components with rubber bushings should be tightened with the weight of the vehicle on the suspension, at normal height. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bush- ing wear may occur. Rubber bushings must never be lubricated.

(1) Support the axle on a suitable lifting device. (2) Secure axle to lifting device. (3) Position the axle under the vehicle. (4) Install springs, retainer clip and bolts. (5) Raise axle and align it with the spring pads.

DR FRONT AXLE - 9 1/4 AA (Continued)

FRONT AXLE - 9 1/4 AA

3 - 49

(6) Position upper and lower suspension arms in the axle brackets. Install bolts, nuts and align the suspension alignment cams to the reference marks. Do not tighten at this time.

(7) Connect track bar to the axle bracket and

install the bolt. Do not tighten at this time.

(8) Install shock absorber and tighten bolts to 121

N·m (89 ft. lbs.).

(9) Install stabilizer bar link to the axle bracket.

Tighten the nut to 68 N·m (50 ft. lbs.).

(10) Install drag link and tie rod to the steering knuckles and tighten the nuts to 108 N·m (80 ft. lbs.).

(11) Install ABS wheel speed sensors. (12) Install rotors and brake calipers. (13) Connect the axle vent hose. (14) Install front propeller shaft. (15) Check and add differential lubricant, if neces-

sary.

(16) Install wheel and tire assemblies. (17) Remove lower the vehicle. (18) Tighten upper suspension arm nuts at axle to 149 N·m (110 ft. lbs.). Tighten upper suspension arm nuts at frame to 149 N·m (110 ft. lbs.).

(19) Tighten lower suspension arm nuts at axle to 190 N·m (140 ft. lbs.). Tighten the lower suspension arm nuts at frame to 190 N·m (140 ft. lbs.).

(20) Tighten track bar bolt at the axle bracket to

176 N·m (130 ft. lbs.).

(21) Check front wheel alignment.

ADJUSTMENTS

Ring and pinion gears are supplied as matched sets only. Compensation for pinion depth variance is achieved with a select shim. The shim is located between the rear pinion bearing and the pinion gear head.

PINION DEPTH MEASUREMENT AND ADJUSTMENT Measurements are taken with pinion bearing cups and pinion bearings installed in the housing. Take measurements with Pinion Gauge Set and Dial Indi- cator C-3339 (Fig. 1).

(1) Assemble Pinion Height Block 6739, Pinion Block 8878 and rear pinion bearing onto Screw 6741
(Fig. 1).

(2) Insert assembled height gauge components, rear bearing and screw into the housing through pin- ion bearing cups (Fig. 2).

(3) Install

front pinion bearing and install the Cone-nut 6740 hand tight. Then check tool rotating torque with an inch pound torque wrench. The rotat- ing torque should be 1.7-2.26 N·m (15-20 in. lbs.)

(4) Place Arbor Disc 8289 on Arbor D-115-3 in posi-

tion in the housing side bearing cradles (Fig. 3).

Fig.1PINIONGEARDEPTHGAUGETOOLS

1 - DIAL INDICATOR 2 - ARBOR 3 - PINION HEIGHT BLOCK 4 - CONE 5 - SCREW 6 - PINION BLOCK 7 - SCOOTER BLOCK 8 - ARBOR DISC

Fig.2PINIONHEIGHTBLOCK

1. PINION HEIGHT BLOCK 2. PINION BLOCK

(5) Install differential bearing caps on arbor discs and snug the bearing cap bolts. Then cross tighten cap bolts to 85 N·m (63 ft. lbs.).

FRONT AXLE - 9 1/4 AA

3 - 50
FRONT AXLE - 9 1/4 AA (Continued)

NOTE: Arbor should rotate freely in the arbor disc.

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Fig.3GAUGETOOLSINHOUSING

1. PINION HEIGHT BLOCK 2. PINION BLOCK 3. ARBOR 4. ARBOR DISCS

Fig.4PINIONDEPTHMEASUREMENT

1. DIAL INDICATOR 2. ARBOR 3. SCOOTER BLOCK

(6) Assemble Dial Indicator C-3339 into Scooter

Block D-115-2 and secure set screw.

(7) Position Scooter Block/Dial Indicator flush on the pinion height block. Hold scooter block and zero the dial indicator.

(8) Slowly slide the scooter block across the pinion height block over to the arbor (Fig. 4). Move the scooter block till dial indicator crests the arbor, then record the highest reading.

(9) Select a shim equal to the dial indicator read-

ing.

(10) Install the select shim between the rear pin-

ion bearing and the pinion gear head.

DIFFERENTIAL CASE BEARING PRELOAD AND GEAR BACKLASH

Backlash is adjusted by moving the adjusters in and out or both. By moving the adjusters the case/ ring gear will move closer or further away from the pinion. In most cases this adjustment can be used to achieve the correct gear tooth pattern and set the case bearing preload.

(1) Remove adjuster lock bolts and adjuster locks

(Fig. 5).

(2) Loosen the differential bearing caps. (3) Slide differential case toward the pinion gear until the gears make contact/zero backlash. If zero backlash cannot be obtained, turn the pinion side adjuster until zero backlash is obtained.

(4) Holding the differential case toward the pinion gear, turn bearing adjusters with Spanner Wrench

Fig.5ADJUSTERLOCKBOLT

1 - DIFFERENTIAL CASE 2 - ADJUSTER LOCK 3 - ADJUSTER LOCK BOLT 4 - BEARING CAP BOLT

8883 until they make contact with the differential bearings/cups.

(5) Back off the ring gear side adjuster 4 holes, to

obtain initial ring gear backlash.

DR FRONT AXLE - 9 1/4 AA (Continued)

FRONT AXLE - 9 1/4 AA

3 - 51

(6) Install ring gear side adjuster lock and bolt. Do

not tighten adjuster lock bolt at this time.

(7) Tighten pinion gear

side adjuster

firmly

against the differential case bearing cup.

(8) Rotate the pinion several times to seat the dif-

ferential bearings.

(9) Loosen pinion gear side adjuster until it is no longer in contact with the bearing cup, then tighten it until it makes contact. (10) Tighten pinion gear side adjuster an addi- tional:† New Bearings: 6 Adjuster Holes † Original Bearings: 4 Adjuster Holes (11) Install pinion gear side adjuster lock and bolt.

Do not tighten adjuster lock bolt at this time.

(12) Tighten bearing cap bolts to 85 N·m (63 ft.

GEAR TOOTH CONTACT PATTERN

Gear tooth contact pattern is used to verify the cor- rect running position of the ring and pinion gears. This will produce low noise and long gear life. Gears which are not positioned properly may be noisy and have shortened gear life.

(1) Wipe clean each tooth of the ring gear. (2) Apply gear marking compound to all of the ring

gear teeth.

tion.

(3) Verify bearing cap bolts are torque to specifica-

(4) Apply the brakes lightly to create a 14 N·m (10

ft. lbs.) pinion rotating torque.

(5) Rotate the pinion/pinion yoke 4 full revolutions

in each directions.

(6) Read gear tooth contact pattern: † Gear contact pattern is correct (Fig. 7). Backlash

(13) Tighten adjuster lock bolts to 25 N·m (18 ft.

and pinion depth is correct.

lbs.).

lbs.).

(14) Measure ring gear backlash with a Dial Indi- cator C-3339 and Dial Indicator Stud L-4438 at eight points around the drive side of the ring gear (Fig. 6). The backlash should be 0.08-0.25 mm (0.003-0.010
in) with a preferred backlash of 0.13-0.18 mm (0.005- 0.007 in).

NOTE: Backlash measurement should not vary more than 0.05 mm (0.002 in) between measuring points. If measurement does vary inspect the gears for burrs, the differential case flange and ring gear mounting.

Fig.7CORRECTCONTACTPATTERN

† Ring gear too far away from pinion gear (Fig. 8). Decrease backlash, by moving the ring closer to the pinion gear using the adjusters.

Fig.6RINGGEARBACKLASH

1 - DIAL INDICATOR 2 - RING GEAR

Fig.8INCORRECTBACKLASH

1 - COAST SIDE TOE 2 - DRIVE SIDE HEEL

FRONT AXLE - 9 1/4 AA

3 - 52
FRONT AXLE - 9 1/4 AA (Continued) † Ring gear too close to pinion gear (Fig. 9). Increase backlash, by moving the ring away from the pinion gear using the adjusters.

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Fig.11INCORRECTBACKLASH

1 - DRIVE SIDE TOE 2 - COAST SIDE TOE

Fig.9INCORRECTBACKLASH

1 - DRIVE SIDE TOE 2 - COAST SIDE HEEL

† Ring gear too far away from pinion gear (Fig. 10). Decrease backlash, by moving the ring closer to the pinion gear using the adjusters.

Fig.12LOWPINIONHEIGHT

Fig.13HIGHPINIONHEIGHT

Fig.10INCORRECTBACKLASH

1 - DRIVE SIDE HEEL 2 - COAST SIDE HEEL

† Ring gear too close to pinion gear (Fig. 11). Increase backlash, by moving the ring away from the pinion gear using the adjusters. † Pinion gear set too low (Fig. 12). Increase pinion gear height, by increasing the pinion depth shim thickness. † Pinion gear set too high (Fig. 13). Decrease pin- ion depth, by decreasing the pinion depth shim thick- ness.

DR FRONT AXLE - 9 1/4 AA (Continued) SPECIFICATIONS

AXLE SPECIFICATIONS

FRONT AXLE - 9 1/4 AA

3 - 53

DESCRIPTION

Axle Ratio

Ring Gear Diameter Ring Gear Backlash

Pinion Bearing Preload - New Bearing

Pinion Bearing Preload - Original Bearing

Pinion Bearing Preload + Differential Case Bearing

Preload - New Bearing

Pinion Bearing Preload + Differential Case Bearing

Preload - Original Bearing

SPECIFICATION

3.73, 4.10

235 mm (9.25 in.)

0.13-0.18 mm (0.005-0.007 in.)

1.7-2.8 N·m (15-25 in. lbs.) 1.1-2.2 N·m (10-20 in. lbs.)

3.4-5.6 N·m (30-50 in. lbs.)

2.8-5.1 N·m (25-45 in. lbs.)

TORQUE SPECIFICATIONS

DESCRIPTION Fill Hole Plug

Differential Cover Bolts

Bearing Cap Bolts Ring Gear Bolts

Axle Nut

Pinion Shaft Lock Bolt

Adjuster Lock Bolt

SPECIAL TOOLS

N·m 32
40
85
140
356
52
25

Ft. Lbs.

In. Lbs.

24
30
63
103
263
38
18

INSTALLERC-3095-A

DIALINDICATORSTUDL-4438

DIALINDICATORSETC-3339

HANDLEC-4171

FRONT AXLE - 9 1/4 AA

3 - 54
FRONT AXLE - 9 1/4 AA (Continued)

DR

SEALINSTALLER8882

PINIONDEPTHSET6730

INSTALLERD-146

ARBORDISCS8289

SPLITTER1130

BRIDGE938

PINIONBLOCK8878

BEARINGINSTALLER8881

DR FRONT AXLE - 9 1/4 AA (Continued)

FRONT AXLE - 9 1/4 AA

3 - 55

PINIONINSTALLER8982

SEALINSTALLER8885

REMOVER/EXTRACTOR6310

RECEIVER8498

PULLERC-293-PA

CUPINSTALLER8886

PINIONDRIVER8976

PLUG8888

FRONT AXLE - 9 1/4 AA

3 - 56
FRONT AXLE - 9 1/4 AA (Continued)

DR

AXLE SHAFTS REMOVAL

(1) Remove wheel and tire assembly. (2) Remove brake caliper, rotor and ABS wheel

speed sensor if equipped.

(3) Remove axle shaft cotter pin, hub nut and

washer (Fig. 14).

ADAPTERS8879

ADJUSTERWRENCH8883

Fig.14AXLENUT

1 - AXLE NUT 2 - AXLE 3 - COTTER PIN

(4) Remove the four hub bearing bolts (Fig. 15)

from the back of the steering knuckle.

(5) Remove hub bearing from the steering knuckle. (6) Remove axle shaft from steering knuckle and axle housing.

(Fig. 16)

FLANGEWRENCH8979

FLANGEPULLER8992

DISASSEMBLY

Single cardan U-joint components are not service-

able. If defective they must be replaced as a unit.

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

(1) Remove the bearing cap retaining snap rings

(Fig. 17).

NOTE: Saturate the bearing caps with penetrating oil prior to removal.

(2) Locate a socket with an inside diameter that is larger than the bearing cap. Place the socket (receiv- er) against the yoke and around the perimeter of the bearing cap to be removed.

DR AXLE SHAFTS (Continued)

FRONT AXLE - 9 1/4 AA

3 - 57

Fig.15HUBBEARINGBOLTS

1 - STUB SHAFT 2 - BEARING BOLTS 3 - AXLE SHAFT

Fig.17AXLESHAFTOUTERU-JOINT

1 - SHAFT YOKE 2 - BEARING CAP 3 - SNAP RINGS 4 - BEARING CAP 5 - SPINDLE YOKE 6 - BEARING 7 - BEARING CAP 8 - SNAP RINGS 9 - BEARING CAP

Fig.16STEERINGKNUCKLE

1 - KNUCKLE 2 - AXLE SHAFT

(3) Locate a socket with an outside diameter that is smaller than the bearing cap. Place the socket (driver) against the opposite bearing cap.

(4) Position the yoke with the sockets in a vise

(Fig. 18).

(5) Tighten the vise jaws to force the bearing cap

into the larger socket (receiver).

(6) Release the vise jaws. Remove the sockets and bearing cap that was partially forced out of the yoke.

Fig.18YOKEBEARINGCAP

1 - LARGE-DIAMETER SOCKET WRENCH 2 - VISE 3 - SMALL-DIAMETER SOCKET WRENCH

(7) Repeat the above procedure for the remaining bearing cap and remove spider from the propeller shaft yoke.

FRONT AXLE - 9 1/4 AA

3 - 58
AXLE SHAFTS (Continued) ASSEMBLY

(1) Pack the bearing caps 1/3 full of wheel bearing lubricant. Apply extreme pressure (EP), lithium-base lubricant to aid in installation.

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

(3) Place the socket (driver) against one bearing

cap. Position the yoke with the socket in a vise.

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

(5) Install the bearing cap retaining clips. (6) Install axle shaft.

INSTALLATION

(1) Clean axle shaft and apply a thin film of Mopar Wheel Bearing Grease to the shaft splines and hub bore.

(2) Install axle shaft through the steering knuckle

and into the differential side gears (Fig. 19).

CAUTION: Do not damage axle shaft seal during axle installtion.

Fig.19AXLESHAFT

1 - AXLE YOKE 2 - AXLE SHAFT 3 - KNUCKLE

(3) Install hub bearing in the knuckle. (4) Install hub bearing bolts and tighten to 202

N·m (149 ft. lbs.).

and caliper.

(5) Install ABS wheel speed sensor, brake rotor

(6) Install axle washer and nut. Tighten axle nut

to 179 N·m (132 ft. lbs.).

DR

(7) Rotate axle several 5 to 10 times to seat the

wheel bearing.

(263 ft. lbs.).

new cotter pin.

(8) Tighten axle nut to final torque of 356 N·m

(9) Align nut to next cotter pin hole and install

(10) Install wheel and tire assembly.

AXLE SHAFT SEALS REMOVAL

(1) Remove hub bearings and axle shafts. (2) Remove differential from differential housing. (3) Remove differential bearing adjusters (Fig. 20).

Fig.20ADJUSTERS

1 - DIFFERENTIAL CASE BEARING ADJUSTERS 2 - DIFFERENTIAL HOUSING

(4) Remove axle seals (Fig. 21)

located behind

adjusters with Receiver 8498 and Extractor 6310. (5) Install Receiver 8498 into the adjuster bore. (6) Install Extractor Rod 6310 with Extractor Foot 6310-9 through the receiver and the axle seal (Fig. 22).

(7) Install Extractor Plate 6310-2 and Nut 6310-7

on the extractor rod.

(8) Tighten nut on the extractor rod (Fig. 23) and

pull the seal out and into the receiver.

INSTALLATION

(1) Install axle seal on Installer Cups 8885-2 and

position cups with seals into the housing.

NOTE: Seal are installed with the axle guide facing outward.

DR AXLE SHAFT SEALS (Continued)

FRONT AXLE - 9 1/4 AA

3 - 59

Fig.21AXLESHAFTSEAL

Fig.23SEALEXTRACTOR

1 - ADJUSTER THREADS 2 - SEAL

1 - EXTRACTOR ROD 2 - EXTRACTOR NUT

Fig.22SEALRECEIVER

Fig.24AXLESEALINSTALLER

1 - RECEIVER 2 - EXTRACTOR FOOT

1 - INSTALLER CUP 2 - INSTALLER TURNBUCKLE 3 - INSTALLER CUP

(2) Install Turnbuckle 8885-1 (Fig. 24)

into the installer cups and expand the turnbuckle until the seal bottom out in the housing.

(3) Install differential into the axle housing. (4) Install axle shaft and hub bearings

3 - 60

FRONT AXLE - 9 1/4 AA

DR

PINION SEAL REMOVAL

(7) Remove pinion flange with Pinion Flange

Puller 8992 (Fig. 27).

(1) Mark the propeller shaft and pinion flange for

installation reference.

(2) Remove propeller shaft. (3) Remove hub bearings and axle shafts. (4) Rotate pinion gear three or four times. (5) Measure and record the torque necessary to rotate (Fig. 25) the pinion gear with an inch pound torque wrench.

Fig.27PINIONFLANGEPULLER

1 - PINION FLANGE 2 - PULLER

(8) Remove pinion shaft seal with a pry tool or

slide hammer mounted screw.

INSTALLATION

(1) Install new pinion seal with Installer 8882 and

Handle C-4171 (Fig. 28).

Fig.25PINIONROTATINGTORQUE

1 - PINION FLANGE 2 - TORQUE WRENCH

(6) Hold pinion flange with Flange Wrench 8979
(Fig. 26) and remove pinion flange nut and washer.

Fig.28PINIONSEALINSTALLER

1 - HANDLE 2 - INSTALLER

(2) Apply a light coat of teflon thread sealant to

the pinion flange splines.

(3) Lightly tap the pinion flange onto the pinion

until a few threads are showing.

(4) Install flange washer and new pinion nut. (5) Hold flange with Flange Wrench 8979 and tighten pinion nut until pinion end play is taken up.

(6) Rotate pinion several times to seat bearings. (7) Measure pinion rotating torque with an inch pound torque wrench and compare it to recorded measurement. Tighten pinion nut in small incre-

Fig.26FLANGEWRENCH

1 - PINION FLANGE 2 - WRENCH

DR PINION SEAL (Continued)

ments, until pinion rotating torque is 0.40-0.57 N·m (3-5 in. lbs.) greater than recorded measurement.

(8) Rotate pinion several times then verify pinion

rotating torque again.

(9) Install axle shafts and hub bearings. (10) Install propeller shaft with reference marks

aligned.

DIFFERENTIAL DESCRIPTION

The differential case is a one-piece design. The dif- ferential pinion shaft is retained with a snap ring. Differential bearing preload and ring gear backlash is adjusted by the use of adjusters. The adjuster are between the differential bearings and the differential housing. Pinion bearing preload is set and main- tained by the use of a collapsible spacer. The stamped steel cover provides a means for inspection and servicing the differential.

OPERATION

During straight-ahead driving, the differential pin- ion gears do not rotate on the pinion mate shaft. This occurs because input torque applied to the gears is divided and distributed equally between the two side gears. As a result, the pinion gears revolve with the pinion mate shaft but do not rotate around it (Fig. 29).

FRONT AXLE - 9 1/4 AA

3 - 61

pinion gears is not divided equally. The pinion gears now rotate around the pinion mate shaft in opposite directions. This allows the side gear and axle shaft attached to the outside wheel to rotate at a faster speed.

Fig.30DIFFERENTIAL-ONTURNS

1 - PINION GEARS ROTATE ON PINION SHAFT

REMOVAL

(1) Remove differential housing cover and drain

lubricant from the housing.

(2) Remove hub bearings and axle shafts. (3) Remove adjuster lock bolts and adjuster locks

(Fig. 31).

Fig.29DIFFERENTIAL-STRAIGHTAHEADDRIVING 1 - IN STRAIGHT AHEAD DRIVING EACH WHEEL ROTATES AT 100% OF CASE SPEED 2 - PINION GEAR 3 - SIDE GEAR 4 - PINION GEARS ROTATE WITH CASE

When turning corners, the outside wheel must travel a greater distance than the inside wheel to complete a turn. To accomplish this, the differential allows the axle shafts to turn at unequal speeds (Fig. 30). In this instance, the input torque applied to the

Fig.31ADJUSTERSANDLOCKS

1 - ADJUSTER LOCK BOLT 2 - ADJUSTER LOCK 3 - ADJUSTER 4 - BEARING CAP

3 - 62
FRONT AXLE - 9 1/4 AA DIFFERENTIAL (Continued)

(4) Mark bearing caps left and right for installa-

(5) Remove bearing cap bolts and remove bearing

tion reference.

caps.

(6) Loosen differential bearing adjusters (Fig. 32)

with Spanner Wrench 8883.

DR

(3) Rotate differential pinion gears to differential window and remove pinion gears and thrust washers (Fig. 34).

Fig.34PINIONGEAR

1 - DIFFERENTIAL WINDOW 2 - PINION GEAR 3 - THRUST GEAR

(4) Remove differential side gears and thrust

washers (Fig. 35).

Fig.32ADJUSTERS

1 - BEARING CUP 2 - ADJUSTER 3 - BEARING CUP 4 - ADJUSTER

(7) Remove differential case from the housing. (8) Remove bearing cups and tag them left and

right for installation reference.

DISASSEMBLY

(1) Remove pinion shaft lock bolt. (2) Remove pinion shaft (Fig. 33).

Fig.35SIDEGEARS

1 - SIDE GEAR 2 - SIDE GEAR 3 - PINION GEARS

Fig.33PINIONSHAFT

1 - PINION SHAFT 2 - PUNCH 3 - PINION GEAR 4 - SIDE GEAR

DR DIFFERENTIAL (Continued) ASSEMBLY NOTE: If the same gears and thrust washers are being used, install them into their orignial locations.

(1) Lubricate all differential components with axle

to 52 N·m (38 ft. lbs.).

lubricant.

ers (Fig. 36).

(2) Install differential side gears and thrust wash-

FRONT AXLE - 9 1/4 AA

3 - 63

(4) Align hole in the pinion gears with hole in the

differential case.

(5) Install pinion shaft. (6) Install new pinion shaft lock bolt and tighten

INSTALLATION

(1) Clean the housing cavity with a flushing oil,

light engine oil or lint free cloth.

CAUTION: Do not use water, steam, kerosene or gasoline for cleaning.

(2) Lubricate differential case bearing. (3) Install differential case with bearings cups into

the housing.

(4) Install bearing caps and bolts (Fig. 38). Tighten

the bearing cap bolts finger-tight.

NOTE: Do not torque bearing cap and bolts at this time.

Fig.36SIDEGEARS

1 - DIFFERENTIAL WINDOW 2 - SIDE GEAR

(3) Rotate the one pinion gear with thrust washer into the differential case (Fig. 37). Then rotate the other pinion gear with thrust washer into the differ- ential case.

Fig.38CASEBEARINGCAP

1 - DIFFERENTIAL HOUSING 2 - BEARING CAP 3 - ADJUSTER

(5) Slide differential case toward the pinion gear until the gears make contact/zero backlash. If zero backlash cannot be obtained, turn the pinion side adjuster until zero backlash is obtained.

(6) Holding the differential case toward the pinion gear, turn bearing adjusters with Spanner Wrench 8883 until they make contact with the differential bearings/cups.

Fig.37PINIONGEAR

1 - DIFFERENTIAL WINDOW 2 - SIDE GEARS 3 - PINION GEAR

3 - 64
FRONT AXLE - 9 1/4 AA DIFFERENTIAL (Continued)

DR

(7) Back off the ring gear side adjuster 4 holes, to

obtain initial ring gear backlash.

(8) Install ring gear side adjuster lock and bolt. Do

not tighten adjuster lock bolt at this time.

(9) Tighten pinion gear

side adjuster

firmly

against the differential case bearing cup.

(10) Rotate the pinion several times to seat the dif-

ferential bearings.

(11) Loosen pinion gear side adjuster until it is no

longer in contact with the bearing cup.

(12) Tighten pinion gear side adjuster until it just

makes contact with the bearing cup. (13) Tighten pinion gear side adjuster an addi- tional:† New Bearings: 6 Adjuster Holes † Original Bearings: 4 Adjuster Holes (14) Install pinion gear side adjuster lock and bolt.

Do not tighten adjuster lock bolt at this time.

(15) Tighten bearing cap bolts to 85 N·m (63 ft.

(16) Tighten adjuster lock bolts to 25 N·m (18 ft.

lbs.).

lbs.) (Fig. 39).

(17) Measure ring gear backlash and check gear tooth contact pattern. Refer to Adjustments for pro- cedure.

(18) Install axle shafts and hub bearings. (19) Install differential housing gasket and cover.

Tighten cover bolts to 40 N·m (30 ft. lbs.).

(20) Fill differential with lubricant, refer to Lubri- cation & Maintenance for capacity and lubricant type.

(21) Install fill plug and tighten to 32 N·m (24 ft.

lbs.).

DIFFERENTIAL CASE BEARINGS REMOVAL

(1) Remove the differential case from the housing. (2) Install Plug 8888 into the end of the case. (3) Remove differental case bearings with Bearing

Splitter 1130 and Bridge 938 (Fig. 40).

Fig.39ADJUSTERLOCKBOLT

1 - DIFFERENTIAL CASE 2 - ADJUSTER LOCK 3 - ADJUSTER LOCK BOLT 4 - BEARING CAP BOLT

Fig.40DIFFERENTIALCASEBEARING

1 - BRIDGE 2 - SPLITTER 3 - BEARING 4 - PLUG

DR DIFFERENTIAL CASE BEARINGS (Continued) INSTALLATION

(1) Set differential case on Plug 8888. (2) Install differenial case bearings with Installer

8881 and Handle C-4171 (Fig. 41).

FRONT AXLE - 9 1/4 AA

3 - 65

Fig.42RINGGEAR

1 - DIFFERENTIAL CASE 2 - RING GEAR 3 - HAMMER

Fig.43FLANGEWRENCH

1 - PINION FLANGE 2 - WRENCH

(9) Remove pinion flange from pinion with Pinion

Flange Puller 8992 (Fig. 44).

(10) Remove pinion gear from housing with Pinion

Driver 8976 and a hammer (Fig. 45).

NOTE: Thread drive on shaft until it bottoms out.

(11) Remove pinion seal with a slide hammer or

pry bar.

(12) Remove and discard front pinion bearing

CAUTION: Do not reuse front pinion bearing/cup.

(13) Remove collapsible spacer from the pinion

shaft.

Fig.41DIFFERENTIALCASEBEARINGS

1 - HANDLE 2 - DIFFERENTIAL CASE 3 - BEARING 4 - INSTALLER

(3) Install differentail case into housing.

PINION GEAR/RING GEAR REMOVAL

NOTE: The ring and pinion gears are service in a matched set. Never replace the ring gear/pinion gear without replacing the other matching gear.

(1) Mark pinion flange and propeller shaft for

installation alignment.

(2) Disconnect propeller shaft from pinion flange

and remove propeller shaft.

(3) Remove axle shafts. (4) Remove differential from housing. (5) Place differential case in a vise with soft metal

(6) Remove bolts holding ring gear to differential

jaw protectors

case.

(7) Drive ring gear from differential case with a

soft hammer (Fig. 42).

(8) Hold pinion flange with Flange Wrench 8979
(Fig. 43) and remove pinion flange nut and washer.

FRONT AXLE - 9 1/4 AA

3 - 66
PINION GEAR/RING GEAR (Continued)

DR

Fig.44PINIONFLANGEPULLER

1 - PINION FLANGE 2 - PULLER

Fig.45PINIONDRIVER

1 - PINION SHAFT 2 - PINION DRIVER

Fig.46REARPINIONBEARING

1 - PULLER 2 - VISE 3 - PINION SHAFT 4 - ADAPTER BLOCKS

INSTALLATION

(1) Install front pinion bearing cup (Fig. 47) with

Installer D-146 and Handle C-4171.

(14) Remove rear pinion bearing with Puller

C-293-PA and Adapters 8879 (Fig. 46).

(15) Remove pinion depth shim from the pinion

gear shaft and record thickness of the shims.

(16) Remove front pinion bearing cup from the

housing with a punch and hammer and discard.

CAUTION: Do not reuse front pinion bearing/cup.

(17) Remove rear pinion bearing cup from the if bearing is

housing with a punch and hammer, replaced.

Fig.47FRONTPINIONBEARINGCUP

1 - INSTALLER 2 - HANDLE

DR PINION GEAR/RING GEAR (Continued)

(2) Install rear pinion bearing cup (Fig. 48) with if bearing is

Installer 8886 and Handle C-4171, replaced.

FRONT AXLE - 9 1/4 AA

3 - 67

(4) Install rear pinion bearing (Fig. 50) with

Installer C-3095-A and a press.

Fig.48REARPINIONBEARINGCUP

1 - INSTALLER 2 - HANDLE

1 - PRESS 2 - INSTALLER 3 - PINION GEAR 4 - REAR PINION BEARING

(3) Install pinion depth shim (Fig. 49) on the pin-

ion gear shaft.

(5) Install new collapsible spacer (Fig. 51).

Fig.50REARPINIONBEARING

Fig.49PINIONDEPTHSHIM

1 - PINION DEPTH SHIM 2 - PINION GEAR

Fig.51COLAPSIBLESPACER

1 - COLAPSIBLE SPACER 2 - PINION GEAR 3 - REAR PINION BEARING

(6) Lubricate pinion and bearings.

FRONT AXLE - 9 1/4 AA

3 - 68
PINION GEAR/RING GEAR (Continued)

(7) Install pinion into the housing and place front pinion bearing onto the pinion shaft. Draw the pinion shaft into the front bearing with Installer 8982 (Fig. 52).

DR

† New Pinion Bearings: 1.7-2.8 N·m (15-25 in. lbs.)† Original Pinion Bearings: 1.1-2.2 N·m (10-20
in. lbs.)

Fig.52PINIONGEARINSTALLER

1 - INSTALLER 2 - DIFFERENTIAL HOUSING

(8) Install new pinion seal (Fig. 53) with Installer

8882 and Handle C-4171.

Fig.54PINIONROTATINGTORQUE

1 - PINION FLANGE 2 - TORQUE WRENCH

(15) Rotate pinion several times then verify pinion

rotating torque again.

(16) Position the ring gear on differential case and

start two new ring gear bolts.

(17) Install the rest of the new ring gear bolts and

tighten them alternately to seat the ring gear.

(18) Torque ring gear bolts to 140 N·m (103 ft.

lbs.).

(19) Install differential in housing. (20) Measure final rotating torque with an inch pound torque wrench. The final pinion rotating torque plus differential case bearing preload is: † New Bearings: 3.4-5.6 N·m (30-50 in. lbs.) † Original Bearings: 2.8-5.1 N·m (25-45 in. lbs.) (21) Install axle shafts. (22) Verify ring gear backlash and gear contact

(23) Install the propeller shaft with the reference

pattern.

marks aligned.

(24) Install differential cover with gasket and

tighten to 40 N·m (30 ft. lbs.).

(25) Fill differential with fluid and tighten fill plug

to 32 N·m (24 ft. lbs.).

Fig.53PINIONSEALINSTALLER

1 - HANDLE 2 - INSTALLER

(9) Apply a light coat of teflon sealant to the pin-

ion flange splines.

(10) Hold pinion and lightly tap the pinion flange onto the pinion shaft, until a few threads are show- ing.

(11) Install pinion flange washer and new pinion

nut.

(12) Hold pinion flange with Flange Wrench 8979

and tighten pinion nut until end play is taken up. (13) Rotate pinion several times to seat bearings. (14) Measure pinion rotating torque with an inch pound torque wrench (Fig. 54). Tighten pinion nut in small increments until pinion rotating torque is:

DR

REAR AXLE - 9 1/4

3 - 69

REAR AXLE - 9 1/4

TABLE OF CONTENTS

page

page

REAR AXLE - 9 1/4

DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 69
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
DIAGNOSIS AND TESTING . . . . . . . . . . . . . . . . 69
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 74
ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . 74
SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . 79
SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . 80

AXLE SHAFTS

REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 83

AXLE SHAFT SEALS

REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 84

AXLE BEARINGS

REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 84

PINION SEAL

REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 85

DIFFERENTIAL

DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 86
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . 88
ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 88

DIFFERENTIAL-TRAC-LOK

DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 89
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
DIAGNOSIS AND TESTING . . . . . . . . . . . . . . . . 89
DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . 90
ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

DIFFERENTIAL CASE BEARINGS

REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 94

PINION GEAR/RING GEAR/TONE RING

REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 96

REAR AXLE - 9 1/4
DESCRIPTION

The axle consist of a cast iron center section with axle tubes extending from either side. The tubes are pressed into and welded to the differential housing to form a one-piece axle housing (Fig. 1). The axles are equipped with semi-floating axle shafts, meaning vehicle loads are supported by the axle shaft and bearings. The axle shafts are retained by C-locks in the differential side gears.

OPERATION

The axle receives power from the propeller shaft. The propeller shaft is connected to the pinion gear which rotates the differential through the gear mesh with the ring gear bolted to the differential case. The engine power is transmitted to the axle shafts through the pinion mate and side gears. The side gears are splined to the axle shafts.

DIAGNOSIS AND TESTING

GEAR NOISE

Axle gear noise can be caused by insufficient lubri- cant, incorrect backlash, incorrect pinion depth, tooth

contact, worn/damaged gears, or the carrier housing not having the proper offset and squareness.

Gear noise usually happens at a specific speed range. The noise can also occur during a specific type of driving condition. These conditions are accelera- tion, deceleration, coast, or constant load.

When road testing, first warm-up the axle fluid by driving the vehicle at least 5 miles and then acceler- ate the vehicle to the speed range where the noise is the greatest. Shift out-of-gear and coast through the peak-noise range. If the noise stops or changes greatly:

† Check for insufficient lubricant. † Incorrect ring gear backlash. † Gear damage. Differential side gears and pinions can be checked by turning the vehicle. They usually do not cause noise during straight-ahead driving when the gears are unloaded. The side gears are loaded during vehi- cle turns. A worn pinion shaft can also cause a snap- ping or a knocking noise.

BEARING NOISE

The axle shaft, differential and pinion bearings can all produce noise when worn or damaged. Bearing noise can be either a whining, or a growling sound. Pinion bearings have a constant-pitch noise. This noise changes only with vehicle speed. Pinion bearing

REAR AXLE - 9 1/4

3 - 70
REAR AXLE - 9 1/4 (Continued)

DR

Fig.191/4AXLE

DR REAR AXLE - 9 1/4 (Continued)

REAR AXLE - 9 1/4

3 - 71

1 - HUB 2 - AXLE SHAFT 3 - VENT FITTING 4 - DIFFERENTIAL HOUSING 5 - CUP 6 - FRONT PINION BEARING CONE 7 - NUT 8 - WASHER 9 - COMPANION FLANGE 10 - SEAL 11 - AXLE SHAFT 12 - HUB 13 - STUD 14 - BEARING CUP 15 - REAR PINION BEARING CONE 16 - DIFFERENTIAL BEARING 17 - ADJUSTER 18 - LOCK 19 - BOLT 20 - BEARING CAP 21 - CAP BOLT 22 - BEARING CUP 23 - THRUST WASHER 24 - SIDE GEAR 25 - C-LOCK 26 - DIFFERENTIAL POSITIONS 27 - THRUST WASHER 28 - COVER

noise will be higher pitched because it rotates at a faster rate. Drive the vehicle and load the differen- tial. If bearing noise occurs, the rear pinion bearing is the source of the noise. If the bearing noise is heard during a coast, the front pinion bearing is the source.

Worn or damaged differential bearings usually pro- duce a low pitch noise. Differential bearing noise is similar to pinion bearing noise. The pitch of differen- tial bearing noise is also constant and varies only with vehicle speed.

Axle shaft bearings produce noise and vibration when worn or damaged. The noise generally changes when 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 noise level. Where axle bearing damage is slight, the noise is usually not noticeable at speeds above 30 mph.

LOW SPEED KNOCK

Low speed knock is generally caused by a worn U-joint or by worn side–gear thrust washers. A worn pinion shaft bore will also cause low speed knock.

VIBRATION

Vibration at the rear of the vehicle is usually caused by a: † Damaged drive shaft. † Missing drive shaft balance weight(s). † Worn or out-of-balance wheels. † Loose wheel lug nuts. † Worn U-joint(s).

29 - PLUG 30 - COVER BOLT 31 - WASHER 32 - CLIP 33 - SIDE GEAR 34 - THRUST WASHER 35 - DIFFERENTIAL BEARING CONE 36 - C-LOCK 37 - BOLT 38 - LOCK 39 - BEARING CUP 40 - ADJUSTER 41 - BEARING CUP 42 - BOLT 43 - PINION MATE SHAFT 44 - EXCITER RING 45 - DIFFERENTIAL CASE 46 - RING GEAR BOLT 47 - RING GEAR 48 - PINION 49 - PINION GEAR DEPTH SHIM 50 - PRELOAD COLLAPSIBLE SPACER 51 - SEAL 52 - AXLE SHAFT BEARING 53 - AXLE SHAFT TUBE 54 - AXLE TUBE 55 - AXLE SHAFT BEARING 56 - SEAL

† Loose/broken springs. † Damaged axle shaft bearing(s). † Loose pinion gear nut. † Excessive pinion yoke run out. † Bent axle shaft(s). Check for loose or damaged front-end components or engine/transmission mounts. These components can contribute to what appears to be a rearend vibra- tion. Do not overlook engine accessories, brackets and drive belts.

NOTE: All driveline components should be exam- ined before starting any repair.

DRIVELINE SNAP

A snap or clunk noise when the vehicle is shifted into gear (or the clutch engaged), can be caused by: † High engine idle speed. † Transmission shift operation. † Loose engine/transmission/transfer case mounts. † Worn U-joints. † Loose spring mounts. † Loose pinion gear nut and yoke. † Excessive ring gear backlash. † Excessive 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 vehi- cle on a hoist with the wheels free to rotate. Instruct the helper to shift the transmission into gear. Listen for the noise, a mechanics stethoscope is helpful in isolating the source of a noise.

REAR AXLE - 9 1/4

3 - 72
REAR AXLE - 9 1/4 (Continued)

DIAGNOSTIC CHART

DR

Condition

Possible Causes

Correction

Wheel Noise

1. Wheel loose.

1. Tighten loose nuts.

2. Faulty, brinelled wheel bearing.

2. Replace bearing.

Axle Shaft Noise

1. Misaligned axle tube.

1. Inspect axle tube alignment. Correct as necessary.

2. Bent or sprung axle shaft.

2. Inspect and correct as necessary.

Axle Shaft Broke

1. Misaligned axle tube.

2 Vehicle overloaded.

3. Erratic clutch operation.

4. Grabbing clutch.

Differential Cracked

1. Improper adjustment of the differential bearings.

2. Excessive ring gear backlash.

3. Vehicle overloaded.

4. Erratic clutch operation.

Differential Gears Scored

1. Insufficient lubrication.

2. Improper grade of lubricant.

3. Excessive spinning of one wheel/tire.

1. Replace the broken shaft after correcting tube mis-alignment.

2. Replace broken shaft and avoid excessive weight on vehicle. 3. Replace broken shaft and avoid or correct erratic clutch operation. 4. Replace broken shaft and inspect and repair clutch as necessary.

1. Replace case and inspect gears and bearings for further damage. Set differential bearing pre-load properly.

2. Replace case and inspect gears and bearings for further damage. Set ring gear backlash properly. 3. Replace case and inspect gears and bearings for further damage. Avoid excessive vehicle weight. 4. Replace case and inspect gears and bearings for further damage. Avoid erratic use of clutch.

1. Replace scored gears. Fill differential with the correct fluid type and quantity. 2. Replace scored gears. Fill differential with the correct fluid type and quantity. 3. Replace scored gears. Inspect all gears, pinion bores, and shaft for damage. Service as necessary.

DR REAR AXLE - 9 1/4 (Continued)

REAR AXLE - 9 1/4

3 - 73

Condition

Possible Causes

Correction

Loss Of Lubricant

1. Lubricant level too high.

2. Worn axle shaft seals. 3. Cracked differential housing. 4. Worn pinion seal. 5. Worn/scored yoke. 6. Axle cover not properly sealed.

1. Drain lubricant to the correct level.

2. Replace seals. 3. Repair as necessary. 4. Replace seal. 5. Replace yoke and seal. 6. Remove, clean, and re-seal cover.

Axle Overheating

1. Lubricant level low.

1. Fill differential to correct level.

2. Improper grade of lubricant.

3. Bearing pre-loads too high. 4. Insufficient ring gear backlash.

Gear Teeth Broke

1. Overloading.

2. Erratic clutch operation.

3. Ice-spotted pavement.

4. Improper adjustments.

Axle Noise

1. Insufficient lubricant.

2. Improper ring gear and pinion adjustment.

3. Unmatched ring gear and pinion.

4. Worn teeth on ring gear and/or pinion. 5. Loose pinion bearings. 6. Loose differential bearings.

7. Mis-aligned or sprung ring gear.

8. Loose differential bearing cap bolts.

9. Housing not machined properly.

2. Fill differential with the correct fluid type and quantity. 3. Re-adjust bearing pre-loads. 4. Re-adjust ring gear backlash.

1. Replace gears. Examine other gears and bearings for possible damage.

2. Replace gears and examine the remaining parts for damage. Avoid erratic clutch operation. 3. Replace gears and examine remaining parts for damage. 4. Replace gears and examine remaining parts for damage. Ensure ring gear backlash is correct.

1. Fill differential with the correct fluid type and quantity. 2. Check ring gear and pinion contact pattern. Adjust backlash or pinion depth. 3. Replace gears with a matched ring gear and pinion. 4. Replace ring gear and pinion.

5. Adjust pinion bearing pre-load. 6. Adjust differential bearing pre-load. 7. Measure ring gear run-out. Replace components as necessary. 8. Inspect differential components and replace as necessary. Ensure that the bearing caps are torqued tot he proper specification. 9. Replace housing.

REAR AXLE - 9 1/4

3 - 74
REAR AXLE - 9 1/4 (Continued) REMOVAL

DR

(1) Raise and support the vehicle. (2) Position a lifting device under the axle. (3) Secure axle to device. (4) Remove wheels and tires assemblies. (5) Remove RWAL sensor from the differential

(6) Remove brake hose at the axle junction block. (7) Disconnect parking brake cables and cable

housing.

brackets.

(8) Remove brake calipers and rotors. (9) Remove axle vent hose. (10) Mark propeller shaft and companion flange

for installation alignment reference.

(11) Remove propeller shaft. (12) Remove shock absorbers from axle. (13) Remove U-bolets from axle. (14) Separate the axle from the vehicle.

INSTALLATION

(1) Raise axle with lifting device and align to the

leaf spring centering bolts.

(2) Install axle U-bolts and tighten to 149 N·m

(110 ft. lbs.).

specification.

housing.

brackets.

(3) Install shock absorbers to axle and tighten to

(4) Install the RWAL sensor to the differential

(5) Connect the parking brake cables and cable

(6) Install brake rotors and calipers. (7) Connect brake hose to the axle junction block. (8) Install axle vent hose. (9) Align propeller shaft and pinion companion flange reference marks and tighten companion flange bolts to 115 N·m (85 ft. lbs.).

(10) Install the wheels and tires. (11) Fill differential to specifications. (12) Remove lifting device from axle and lower the

vehicle.

ADJUSTMENTS

Ring gear and pinion are supplied as matched sets only. The identifying numbers for the ring gear and pinion are painted onto the pinion gear shaft (Fig. 2) and the side of the ring gear. A plus (+) number, minus (–) number or zero (0) along with the gear set sequence number (01 to 99) is on each gear. This first number is the amount (in thousandths of an inch) the depth varies from the standard depth setting of a pinion marked with a (0). The next two numbers are the sequence number of the gear set. The standard depth provides the best teeth contact pattern. Refer to Backlash and Contact Pattern for additional infor- mation.

Fig.2PINIONIDNUMBER

1 - VARIANCE NUMBER 2 - SEQUENCE NUMBER

Compensation for

is achieved with select shims. The shims are placed behind the rear pinion bearing. (Fig. 3).

pinion depth variance

Fig.3ADJUSTMENTSHIMLOCATIONS

1 - DIFFERENTIAL HOUSING 2 - COLLAPSIBLE SPACER 3 - PINION BEARING 4 - PINION DEPTH SHIM 5 - PINION GEAR 6 - BEARING CUP

If a new gear set is being installed, note the depth variance painted onto both the original and replace- ment pinion. Add or subtract the thickness of the original depth shims to compensate for the difference in the depth variances. Refer to the Depth Variance chart.

Note where Old and New Pinion Marking columns Intersecting figure represents plus or

intersect. minus the amount needed.

Note the painted number on the shaft of the drive pinion (–1, –2, 0, +1, +2, etc.). The numbers repre-

DR REAR AXLE - 9 1/4 (Continued)

REAR AXLE - 9 1/4

3 - 75

sent thousands of an inch deviation from the stan- dard. If the number is negative, add that value to the required thickness of the depth shims. If the number

is positive, subtract that value from the thickness of the depth shim. If the number is 0 no change is nec- essary.

Original Pinion

Gear Depth

Variance

+4
+3
+2
+1
21
22
23
24

24

+0.008
+0.007
+0.006
+0.005
+0.004
+0.003
+0.002
+0.001

PINION GEAR DEPTH VARIANCE

Replacement Pinion Gear Depth Variance

23

22

21

+1

+2

+3

+0.001

+4

+0.006