(3) Rotate differential pinion gears to differential
window and remove pinion gears and thrust washers
(Fig. 37).
(4) Remove differential side gears and thrust
washers (Fig. 38).
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
lubricant.
(2) Install differential side gears and thrust wash-
ers (Fig. 39).
(3) Rotate the one pinion gear with thrust washer
into the differential case (Fig. 40). Then rotate the
other pinion gear with thrust washer into the differ-
ential case.
Fig. 37 PINION GEAR
1 - DIFFERENTIAL WINDOW
2 - PINION GEAR
3 - THRUST GEAR
Fig. 38 SIDE GEARS
1 - SIDE GEAR
2 - SIDE GEAR
3 - PINION GEARS
Fig. 39 SIDE GEARS
1 - DIFFERENTIAL WINDOW
2 - SIDE GEAR
Fig. 40 PINION GEAR
1 - DIFFERENTIAL WINDOW
2 - SIDE GEARS
3 - PINION GEAR
DRFRONT AXLE - 9 1/4 AA 3 - 73
DIFFERENTIAL (Continued)
(4) Align hole in the pinion gears with hole in the
differential case.
(5) Install pinion shaft.
(6) Installnewpinion shaft lock bolt and tighten
to 52 N´m (38 ft. lbs.).
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. 41). Tighten
the bearing cap bolts finger-tight.
NOTE: Do not torque bearing cap and bolts at this
time.
(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.(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:
²New Bearings:6 Adjuster Holes
²Original 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.
lbs.).
(16) Tighten adjuster lock bolts to 25 N´m (18 ft.
lbs.) (Fig. 42).
(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.).
Fig. 41 CASE BEARING CAP
1 - DIFFERENTIAL HOUSING
2 - BEARING CAP
3 - ADJUSTERFig. 42 ADJUSTER LOCK BOLT
1 - DIFFERENTIAL CASE
2 - ADJUSTER LOCK
3 - ADJUSTER LOCK BOLT
4 - BEARING CAP BOLT
3 - 74 FRONT AXLE - 9 1/4 AADR
DIFFERENTIAL (Continued)
(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. 43).
INSTALLATION
(1) Set differential case on Plug 8888.
(2) Install differenial case bearings with Installer
8881 and Handle C-4171 (Fig. 44).
(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
jaw protectors
(6) Remove bolts holding ring gear to differential
case.
Fig. 43 DIFFERENTIAL CASE BEARING
1 - BRIDGE
2 - SPLITTER
3 - BEARING
4 - PLUG
Fig. 44 DIFFERENTIAL CASE BEARINGS
1 - HANDLE
2 - DIFFERENTIAL CASE
3 - BEARING
4 - INSTALLER
DRFRONT AXLE - 9 1/4 AA 3 - 75
DIFFERENTIAL (Continued)
(7) Drive ring gear from differential case with a
soft hammer (Fig. 45).
(8) Hold pinion flange with Flange Wrench 8979
(Fig. 46) and remove pinion flange nut and washer.(9) Remove pinion flange from pinion with Pinion
Flange Puller 8992 (Fig. 47).
(10) Remove pinion gear from housing with Pinion
Driver 8976 and a hammer (Fig. 48).
NOTE: Thread drive on shaft until it bottoms out.
Fig. 45 RING GEAR
1 - DIFFERENTIAL CASE
2 - RING GEAR
3 - HAMMER
Fig. 46 FLANGE WRENCH
1 - PINION FLANGE
2 - WRENCH
Fig. 47 PINION FLANGE PULLER
1 - PINION FLANGE
2 - PULLER
Fig. 48 PINION DRIVER
1 - PINION SHAFT
2 - PINION DRIVER
3 - 76 FRONT AXLE - 9 1/4 AADR
PINION GEAR/RING GEAR (Continued)
(3) Install pinion depth shim (Fig. 52) on the pin-
ion gear shaft.
(4) Install rear pinion bearing (Fig. 53) with
Installer C-3095-A and a press.(5) Installnewcollapsible spacer (Fig. 54).
(6) Lubricate pinion and bearings.
(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.
55).
Fig. 52 PINION DEPTH SHIM
1 - PINION DEPTH SHIM
2 - PINION GEAR
Fig. 53 REAR PINION BEARING
1 - PRESS
2 - INSTALLER
3 - PINION GEAR
4 - REAR PINION BEARING
Fig. 54 COLAPSIBLE SPACER
1 - COLAPSIBLE SPACER
2 - PINION GEAR
3 - REAR PINION BEARING
Fig. 55 PINION GEAR INSTALLER
1 - INSTALLER
2 - DIFFERENTIAL HOUSING
3 - 78 FRONT AXLE - 9 1/4 AADR
PINION GEAR/RING GEAR (Continued)
(8) Installnewpinion seal (Fig. 56) with Installer
8882 and Handle C-4171.
(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 andnewpinion
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. 57). Tighten pinion nut in
small increments until pinion rotating torque is:
²New Pinion Bearings:1.7-2.8 N´m (15-25 in.
lbs.)
²Original Pinion Bearings:1.1-2.2 N´m (10-20
in. lbs.)
(15) Rotate pinion several times then verify pinion
rotating torque again.
(16) Position the ring gear on differential case and
start twonewring gear bolts.
(17) Install the rest of thenewring 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:
²New Bearings:3.4-5.6 N´m (30-50 in. lbs.)
²Original Bearings:2.8-5.1 N´m (25-45 in. lbs.)
(21) Install axle shafts.
(22) Verify ring gear backlash and gear contact
pattern.
(23) Install the propeller shaft with the reference
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. 56 PINION SEAL INSTALLER
1 - HANDLE
2 - INSTALLER
Fig. 57 PINION ROTATING TORQUE
1 - PINION FLANGE
2 - TORQUE WRENCH
DRFRONT AXLE - 9 1/4 AA 3 - 79
PINION GEAR/RING GEAR (Continued)
REAR AXLE-91/4
TABLE OF CONTENTS
page page
REAR AXLE-91/4
DIAGNOSIS AND TESTING................80
REMOVAL.............................83
INSTALLATION.........................83
ADJUSTMENTS........................83
SPECIFICATIONS.......................90
SPECIAL TOOLS.......................90
AXLE SHAFTS
REMOVAL.............................93
INSTALLATION.........................94
AXLE SHAFT SEALS
REMOVAL.............................94
INSTALLATION.........................94
AXLE BEARINGS
REMOVAL.............................95
INSTALLATION.........................95
PINION SEAL
REMOVAL.............................95
INSTALLATION.........................96
DIFFERENTIAL COVER
REMOVAL.............................97INSTALLATION.........................97
DIFFERENTIAL
REMOVAL.............................97
DISASSEMBLY.........................98
ASSEMBLY............................99
INSTALLATION.........................99
DIFFERENTIAL-TRAC-LOK
DESCRIPTION........................100
OPERATION..........................100
DIAGNOSIS AND TESTING...............100
DISASSEMBLY........................101
ASSEMBLY...........................103
DIFFERENTIAL CASE BEARINGS
REMOVAL............................105
INSTALLATION........................106
PINION GEAR/RING GEAR/TONE RING
REMOVAL............................106
INSTALLATION........................108
REAR AXLE-91/4
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:
²Insufficient lubricant.
²Incorrect ring gear backlash.
²Gear 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 bearingshave 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
heard during a coast, the front pinion bearing is the
source.
Differential bearingsusually produce a low pitch
noise. Differential bearing noise is similar to pinion
bearing noise. The pitch of differential bearing noise
is also constant and varies only with vehicle speed.
Axle shaft bearingsproduce 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.
3 - 80 REAR AXLE-91/4DR
Condition Possible Causes Correction
Differential Cracked 1. Improper adjustment of the
differential bearings.1. Replace case and inspect gears
and bearings for further damage.
Set differential bearing pre-load
properly.
2. Excessive ring gear backlash. 2. Replace case and inspect gears
and bearings for further damage.
Set ring gear backlash properly.
3. Vehicle overloaded. 3. Replace case and inspect gears
and bearings for further damage.
Avoid excessive vehicle weight.
4. Erratic clutch operation. 4. Replace case and inspect gears
and bearings for further damage.
Avoid erratic use of clutch.
Differential Gears Scored 1. Insufficient lubrication. 1. Replace scored gears. Fill
differential with the correct fluid type
and quantity.
2. Improper grade of lubricant. 2. Replace scored gears. Fill
differential with the correct fluid type
and quantity.
3. Excessive spinning of one
wheel/tire.3. Replace scored gears. Inspect all
gears, pinion bores, and shaft for
damage. Service as necessary.
Loss Of Lubricant 1. Lubricant level too high. 1. Drain lubricant to the correct
level.
2. Worn axle shaft seals. 2. Replace seals.
3. Cracked differential housing. 3. Repair as necessary.
4. Worn pinion seal. 4. Replace seal.
5. Worn/scored yoke. 5. Replace yoke and seal.
6. Axle cover not properly sealed. 6. Remove, clean, and re-seal
cover.
Axle Overheating 1. Lubricant level low. 1. Fill differential to correct level.
2. Improper grade of lubricant. 2. Fill differential with the correct
fluid type and quantity.
3. Bearing pre-loads too high. 3. Re-adjust bearing pre-loads.
4. Insufficient ring gear backlash. 4. Re-adjust ring gear backlash.
3 - 82 REAR AXLE-91/4DR
REAR AXLE - 9 1/4 (Continued)