
SEAL INSTALLER 8882
INSTALLER D-146
SPLITTER 1130
BRIDGE 938
PINION DEPTH SET 6730
ARBOR DISCS 8289
PINION BLOCK 8878
BEARING INSTALLER 8881
3 - 54 FRONT AXLE - 9 1/4 AADR
FRONT AXLE - 9 1/4 AA (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).
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 thepinion 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.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. 29 DIFFERENTIAL-STRAIGHT AHEAD DRIVING
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
Fig. 30 DIFFERENTIAL-ON TURNS
1 - PINION GEARS ROTATE ON PINION SHAFT
Fig. 31 ADJUSTERS AND LOCKS
1 - ADJUSTER LOCK BOLT
2 - ADJUSTER LOCK
3 - ADJUSTER
4 - BEARING CAP
DRFRONT AXLE - 9 1/4 AA 3 - 61
PINION SEAL (Continued)

(4) Mark bearing caps left and right for installa-
tion reference.
(5) Remove bearing cap bolts and remove bearing
caps.
(6) Loosen differential bearing adjusters (Fig. 32)
with Spanner Wrench 8883.
(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).(3) Rotate differential pinion gears to differential
window and remove pinion gears and thrust washers
(Fig. 34).
(4) Remove differential side gears and thrust
washers (Fig. 35).
Fig. 32 ADJUSTERS
1 - BEARING CUP
2 - ADJUSTER
3 - BEARING CUP
4 - ADJUSTER
Fig. 33 PINION SHAFT
1 - PINION SHAFT
2 - PUNCH
3 - PINION GEAR
4 - SIDE GEAR
Fig. 34 PINION GEAR
1 - DIFFERENTIAL WINDOW
2 - PINION GEAR
3 - THRUST GEAR
Fig. 35 SIDE GEARS
1 - SIDE GEAR
2 - SIDE GEAR
3 - PINION GEARS
3 - 62 FRONT AXLE - 9 1/4 AADR
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
lubricant.
(2) Install differential side gears and thrust wash-
ers (Fig. 36).
(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.(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. 38). 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.
Fig. 36 SIDE GEARS
1 - DIFFERENTIAL WINDOW
2 - SIDE GEAR
Fig. 37 PINION GEAR
1 - DIFFERENTIAL WINDOW
2 - SIDE GEARS
3 - PINION GEAR
Fig. 38 CASE BEARING CAP
1 - DIFFERENTIAL HOUSING
2 - BEARING CAP
3 - ADJUSTER
DRFRONT AXLE - 9 1/4 AA 3 - 63
DIFFERENTIAL (Continued)

(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. 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. 39 ADJUSTER LOCK BOLT
1 - DIFFERENTIAL CASE
2 - ADJUSTER LOCK
3 - ADJUSTER LOCK BOLT
4 - BEARING CAP BOLT
Fig. 40 DIFFERENTIAL CASE BEARING
1 - BRIDGE
2 - SPLITTER
3 - BEARING
4 - PLUG
3 - 64 FRONT AXLE - 9 1/4 AADR
DIFFERENTIAL (Continued)

(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
housing with a punch and hammer, if bearing is
replaced.
INSTALLATION
(1) Install front pinion bearing cup (Fig. 47) with
Installer D-146 and Handle C-4171.
Fig. 44 PINION FLANGE PULLER
1 - PINION FLANGE
2 - PULLER
Fig. 45 PINION DRIVER
1 - PINION SHAFT
2 - PINION DRIVER
Fig. 46 REAR PINION BEARING
1 - PULLER
2 - VISE
3 - PINION SHAFT
4 - ADAPTER BLOCKS
Fig. 47 FRONT PINION BEARING CUP
1 - INSTALLER
2 - HANDLE
3 - 66 FRONT AXLE - 9 1/4 AADR
PINION GEAR/RING GEAR (Continued)

REAR AXLE-91/4
TABLE OF CONTENTS
page page
REAR AXLE-91/4
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.............................85INSTALLATION.........................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-91/4
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, toothcontact, 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:
²Check for insufficient 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 bearings have a constant-pitch noise. This
noise changes only with vehicle speed. Pinion bearing
DRREAR AXLE - 9 1/4 3 - 69

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:
²Damaged drive shaft.
²Missing drive shaft balance weight(s).
²Worn or out-of-balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent 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:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive 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.
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 - COVER29 - 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
DRREAR AXLE - 9 1/4 3 - 71
REAR AXLE - 9 1/4 (Continued)