
AXLE BEARINGS
REMOVAL
(1) Remove axle shaft flange bolts and remove axle
shaft.
(2) Remove retianer ring (Fig. 16) from the axle
shaft tube.
(3) Remove hub bearing nut locking key (Fig. 17).(4) Remove hub bearing nut with Socket 8954.
(5) Remove hub and bearings from the axle.
(6) Pry out hub bearing seal from the back of the
hub.
NOTE: The inner part of the seal may stay on the
axle tube (Fig. 18). This part must also be removed.
(7) Remove rear bearing.
(8) Remove hub bearing cups with a hammer and
drift.
INSTALLATION
(1) Install outer hub bearing cup with Installer
8961 and Handle C-4171.
(2) Install inner hub bearing cup with Installer
8962 and Handle C-4171.
(3) Pack bearings with the appropriate grease.
(4) Install rear bearing and installnewgrease
seal with Installer 8963 and Handle C-4171.
(5) Slide hub on the axle tube and install front
bearing into the hub.
(6) Install hub bearing nut with Socket 8954 and
tighten to 30 N´m (22 ft. lbs.) while rotating the hub
(Fig. 19).
(7) Back off nut about 30É and align next hub nut
key slot with axle tube key slot and install locking
key.
NOTE: End play should be 0.025-0.25 mm
(0.001-0.010 in.).
(8) Install retainer ring with ring end in the key
slot.
(9) Install new axle shaft gasket and install axle
shaft.
Fig. 16 RETAINER RING
1 - RETAINER RING
2 - LOCKING KEY
3 - BEARING NUT
Fig. 17 LOCKING KEY
1 - BEARING NUT
2 - LOCKING KEY
3 - AXLE TUBE
Fig. 18 INNER PART OF SEAL
1-PRYBAR
2 - AXLE TUBE
3 - REMAINING SEAL
3 - 112 REAR AXLE - 10 1/2 AADR

PINION SEAL
REMOVAL
(1) Remove axle shafts.
(2) Mark propeller shaft and pinion flange for
installation reference and remove shaft.
(3) Rotate pinion gear three or four times.
(4) Measure and record the amount of torque nec-
essary to rotate the pinion gear with an inch pound
torque wrench (Fig. 20).
(5) Hold pinion flange with Flange Wrench 8979
(Fig. 21) and remove pinion flange nut and washer.(6) Remove pinion flange with Pinion Flange
Puller 8992 (Fig. 22).
(7) Remove pinion shaft seal with a pry tool or
slide hammer mounted screw.
INSTALLATION
(1) Installnewpinion seal with Installer 8896 and
Handle C-4171 (Fig. 23).
(2) Apply a light coat of teflon sealant to the pin-
ion flange splines.
(3) Lightly tap the pinion flange onto the pinion
until a few threads are showing.
(4) Install flange washer andnewpinion nut.
(5) Hold flange with Flange Wrench 8979 (Fig. 24)
and tighten pinion nut until pinion end play is taken
up.
Fig. 19 HUB NUT SOCKET
1 - SOCKET
2 - TORQUE WRENCH
Fig. 20 PINION ROTATING TORQUE
1 - PINION FLANGE
2 - TORQUE WRENCH
Fig. 21 FLANGE WRENCH
1 - PINION FLANGE
2 - FLANGE WRENCH
Fig. 22 PINION FLANGE PULLER
1 - PINION FLANGE
2 - PULLER
DRREAR AXLE - 10 1/2 AA 3 - 113
AXLE BEARINGS (Continued)

(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.
(8) Tighten pinion nut in small increments, until
pinion rotating torque is 0.40-0.57 N´m (3-5 in. lbs.)
greater than recorded measurement.
(9) Rotate pinion several times then verify pinion
rotating torque again.
(10) Install axle shafts.
(11) Install propeller shaft with reference marks
aligned.
(12) Check and fill differential if necessary.
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.
25).
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.
26). In this instance, the input torque applied to the
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. 23 PINION SEAL INSTALLER
1 - HANDLE
2 - INSTALLER
Fig. 24 FLANGE WRENCH
1 - FLANGE WRENCH
2 - PINION FLANGE
Fig. 25 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
3 - 114 REAR AXLE - 10 1/2 AADR
PINION SEAL (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 8981 (Fig.
60).
(8) Installnewpinion seal (Fig. 61) with Installer
8896 and Handle C-4171.
(9) Apply a light coat of teflon sealant to the pin-
ion flange splines.
(10) Hold the pinion and lightly tap the pinion
flange onto the pinion, until a few threads are show-
ing.
(11) Install pinion flange washer andnewpinion
nut.
(12) Hold pinion flange with Flange Wrench 8979
(Fig. 62) and tighten pinion nut until pinion 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. 63). 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.
Fig. 60 PINION GEAR INSTALLER
1 - INSTALLER
2 - DIFFERENTIAL HOUSING
Fig. 61 PINION SEAL INSTALLER
1 - HANDLE
2 - INSTALLER
Fig. 62 FLANGE WRENCH
1 - FLANGE WRENCH
2 - PINION FLANGE
Fig. 63 PINION ROTATING TORQUE
1 - PINION FLANGE
2 - TORQUE WRENCH
DRREAR AXLE - 10 1/2 AA 3 - 125
PINION GEAR/RING GEAR/TONE RING (Continued)

REAR AXLE - 11 1/2 AA
TABLE OF CONTENTS
page page
REAR AXLE - 11 1/2 AA
DESCRIPTION........................127
OPERATION..........................127
DIAGNOSIS AND TESTING...............127
REMOVAL............................130
INSTALLATION........................130
ADJUSTMENTS.......................131
SPECIFICATIONS......................135
SPECIAL TOOLS.......................135
AXLE SHAFTS
REMOVAL............................138
INSTALLATION........................138
AXLE BEARINGS
REMOVAL............................138
INSTALLATION........................139
PINION SEAL
REMOVAL............................140
INSTALLATION........................140
DIFFERENTIAL
DESCRIPTION........................141OPERATION..........................141
REMOVAL............................142
DISASSEMBLY........................142
ASSEMBLY...........................143
INSTALLATION........................144
DIFFERENTIAL TRAC-RITE
DESCRIPTION........................145
OPERATION..........................145
DISASSEMBLY........................145
CLEANING...........................146
INSPECTION.........................146
ASSEMBLY...........................147
DIFFERENTIAL CASE BEARINGS
REMOVAL............................148
INSTALLATION........................148
PINION GEAR/RING GEAR/TONE RING
REMOVAL............................149
INSTALLATION........................150
REAR AXLE - 11 1/2 AA
DESCRIPTION
The axle consists of a cast iron center casting dif-
ferential housing with axle shaft tubes extending
from each side. The tubes are pressed into the differ-
ential housing and welded. The design has the cen-
terline of the pinion set below the centerline of the
ring gear. The axle is a full floating axle where the
loads are supported by the axle housing tubes. The
axle has a vent used to relieve internal pressure
caused by lubricant vaporization and internal expan-
sion.
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:
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.
DRREAR AXLE - 11 1/2 AA 3 - 127

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
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.
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. 1. Inspect axle tube alignment.
Correct as necessary.
2. Bent or sprung axle shaft. 2. Inspect and correct as necessary.
3 - 128 REAR AXLE - 11 1/2 AADR
REAR AXLE - 11 1/2 AA (Continued)

(12) Tighten bearing cap bolts to 115 N´m (85 ft.
lbs.).
(13) Tighten adjuster lock bolts to 33 N´m (24 ft.
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. 7).
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.
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 shorten gear life.
(1) Wipe clean each tooth of the ring gear.
(2) Apply gear marking compound to all of the ring
gear teeth.
(3) Verify bearing cap bolts are torque specifica-
tion.
(4) Apply parking brakes lightly to create at 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:²Gear contact pattern correct (Fig. 8). Backlash
and pinion depth is correct.
²Ring gear too far away from pinion gear (Fig. 9).
Decrease backlash, by moving the ring closer to the
pinion gear using the adjusters.
²Ring gear too close to pinion gear (Fig. 10).
Increase backlash, by moving the ring away from the
pinion gear using the adjusters.
Fig. 7 RING GEAR BACKLASH
1 - DIAL INDICATOR
2 - RING GEAR
Fig. 8 CORRECT CONTACT PATTERN
Fig. 9 INCORRECT BACKLASH
1 - COAST SIDE TOE
2 - DRIVE SIDE HEEL
Fig. 10 INCORRECT BACKLASH
1 - DRIVE SIDE TOE
2 - COAST SIDE HEEL
DRREAR AXLE - 11 1/2 AA 3 - 133
REAR AXLE - 11 1/2 AA (Continued)

NOTE: The inner part of the seal may stay on the
axle tube (Fig. 18). This part must also be removed.
(7) Remove rear bearing.
(8) Remove hub bearing cups with a hammer and
drift.
INSTALLATION
(1) Install outer hub bearing cup with Installer
8961 and Handle C-4171.
(2) Install inner hub bearing cup with Installer
8153 and Handle C-4171.
(3) Pack bearings with the appropriate wheel bear-
ing grease.
(4) Install rear bearing and installnewgrease
seal with Installer 8963 and Handle C-4171.
(5) Slide hub on the axle tube and install front
bearing into the hub.
(6) Install hub bearing nut with Socket 8954 and
tighten to 30 N´m (22 ft. lbs.) while rotating the hub
(Fig. 19).
Fig. 16 RETAINER RING
1 - RETAINER RING
2 - LOCKING KEY
3 - BEARING NUT
Fig. 17 LOCKING KEY
1 - BEARING NUT
2 - LOCKING KEY
3 - AXLE TUBE
Fig. 18 INNER PART OF SEAL
1-PRYBAR
2 - AXLE TUBE
3 - REMAINING SEAL
Fig. 19 HUB NUT SOCKET
1 - SOCKET
2 - TORQUE WRENCH
DRREAR AXLE - 11 1/2 AA 3 - 139
AXLE BEARINGS (Continued)