Page 217 of 2627

(9) Remove pinion flange from the pinion with Pin-
ion Flange Puller 8992 (Fig. 52).
(10) Remove pinion gear from housing, with Pinion
Driver 8977 (Fig. 53) and a hammer.
NOTE: Thread the driver on the pinion shaft till 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.
(14) Remove rear pinion bearing with Puller
C-293-PA and Adapter Blocks 8879 (Fig. 54).
(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 cup.
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
going to be replaced.
Fig. 52 PINION FLANGE PULLER
1 - PINION FLANGE
2 - PULLER
Fig. 53 PINION DRIVER
1 - PINION SHAFT
2 - PINION DRIVER
Fig. 54 REAR PINION BEARING
1 - PULLER
2 - VISE
3 - PINION SHAFT
4 - ADAPTER BLOCKS
3 - 136 REAR AXLE - 10 1/2 AADR
PINION GEAR/RING GEAR/TONE RING (Continued)
Page 218 of 2627
INSTALLATION
(1) Install new front pinion bearing cup (Fig. 55)
with Installer 8960 and Handle C-4171.
(2) Install new rear pinion bearing cup (Fig. 56)
with Installer 8959 and Handle C-4171.
(3) Install pinion depth shim (Fig. 57) on the pin-
ion gear shaft.(4) Install rear pinion bearing (Fig. 58) with
Installer MD-998805 and a press.
Fig. 55 FRONT PINION BEARING CUP
1 - INSTALLER
2 - HANDLE
Fig. 56 REAR PINION BEARING CUP
1 - INSTALLER
2 - HANDLE
Fig. 57 PINION DEPTH SHIM
1 - PINION DEPTH SHIM
2 - PINION GEAR
Fig. 58 REAR PINION BEARING
1 - PRESS
2 - INSTALLER
3 - PINION GEAR
4 - REAR PINION BEARING
DRREAR AXLE - 10 1/2 AA 3 - 137
PINION GEAR/RING GEAR/TONE RING (Continued)
Page 219 of 2627

(5) Installnewcollapsible spacer (Fig. 59).
(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 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.
Fig. 59 COLLAPSIBLE SPACER
1 - COLAPSIBLE SPACER
2 - PINION GEAR
3 - REAR PINION BEARING
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
3 - 138 REAR AXLE - 10 1/2 AADR
PINION GEAR/RING GEAR/TONE RING (Continued)
Page 220 of 2627

(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.
(18) Torque ring gear bolts to 237 N´m (175 ft.
lbs.).
(19) If exciter ring was removed, position differen-
tial assembly on differential Plug 8888 (Fig. 64) and
place exciter ring on the differential case.
(20) Install the exciter ring on the differential case
evenly with a hammer and brass punch (Fig. 65).
Drive the ring down until it is seated against the
ring gear.
CAUTION: Do not damage exciter ring teeth during
installation.
(21) Install differential into the housing.
(22) Verify ring gear backlash and gear contact
pattern.
(23) 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.)
(24) Install axle shafts.
(25) Install the propeller shaft with the reference
marks aligned.
(26) Install differential cover with gasket and
tighten bolts to 40 N´m (30 ft. lbs.).
(27) Fill differential with fluid and tighten fill plug
to 32 N´m (24 ft. lbs.).
Fig. 63 PINION ROTATING TORQUE
1 - PINION FLANGE
2 - TORQUE WRENCH
Fig. 64 EXCITER RING
1 - EXCITER RING
2 - RING GEAR
3 - DIFFERENTIAL PLUG
4 - DIFFERENTIAL CASE
Fig. 65 EXCITER RING INSTALLATION
1 - EXCITER RING
2 - PUNSH
3 - RING GEAR
DRREAR AXLE - 10 1/2 AA 3 - 139
PINION GEAR/RING GEAR/TONE RING (Continued)
Page 221 of 2627

REAR AXLE - 11 1/2 AA
TABLE OF CONTENTS
page page
REAR AXLE - 11 1/2 AA
DIAGNOSIS AND TESTING...............140
REMOVAL............................143
INSTALLATION........................144
ADJUSTMENTS.......................144
SPECIFICATIONS......................148
SPECIAL TOOLS.......................148
AXLE SHAFTS
REMOVAL............................152
INSTALLATION........................152
AXLE BEARINGS
REMOVAL............................152
INSTALLATION........................153
PINION SEAL
REMOVAL............................153
INSTALLATION........................154
DIFFERENTIAL
REMOVAL............................155DISASSEMBLY........................155
ASSEMBLY...........................156
INSTALLATION........................157
DIFFERENTIAL TRAC-RITE
DESCRIPTION........................158
OPERATION..........................158
DISASSEMBLY........................158
CLEANING...........................160
INSPECTION.........................160
ASSEMBLY...........................161
DIFFERENTIAL CASE BEARINGS
REMOVAL............................161
INSTALLATION........................161
PINION GEAR/RING GEAR/TONE RING
REMOVAL............................162
INSTALLATION........................164
REAR AXLE - 11 1/2 AA
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. The side gears are loaded dur-
ing turns. They usually do not cause noise during
straight-ahead driving when the gears are unloaded.
A worn pinion 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 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.
LOW SPEED KNOCK
Low speed knock is generally caused by:
²Worn U-joint(s).
²Worn side gear thrust washers.
²Worn pinion shaft bore.
3 - 140 REAR AXLE - 11 1/2 AADR
Page 222 of 2627

VIBRATION
Vibration at the rear of the vehicle is usually
caused by:
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 rear end
vibration. Do not overlook engine accessories, brack-
ets 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 and lis-
ten 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.
Axle Shaft Broke 1. Misaligned axle tube. 1. Replace the broken shaft after
correcting tube mis-alignment.
2 Vehicle overloaded. 2. Replace broken shaft and avoid
excessive weight on vehicle.
3. Erratic clutch operation. 3. Replace broken shaft and avoid or
correct erratic clutch operation.
4. Grabbing clutch. 4. Replace broken shaft and inspect
and repair clutch as necessary.
DRREAR AXLE - 11 1/2 AA 3 - 141
REAR AXLE - 11 1/2 AA (Continued)
Page 223 of 2627

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.
Gear Teeth Broke 1. Overloading. 1. Replace gears. Examine other
gears and bearings for possible
damage.
2. Erratic clutch operation. 2. Replace gears and examine the
remaining parts for damage. Avoid
erratic clutch operation.
3. Ice-spotted pavement. 3. Replace gears and examine
remaining parts for damage.
4. Improper adjustments. 4. Replace gears and examine
remaining parts for damage. Ensure
ring gear backlash is correct.
3 - 142 REAR AXLE - 11 1/2 AADR
REAR AXLE - 11 1/2 AA (Continued)
Page 224 of 2627

Condition Possible Causes Correction
Axle Noise 1. Insufficient lubricant. 1. Fill differential with the correct fluid
type and quantity.
2. Improper ring gear and pinion
adjustment.2. Check ring gear and pinion contact
pattern. Adjust backlash or pinion
depth.
3. Unmatched ring gear and pinion. 3. Replace gears with a matched ring
gear and pinion.
4. Worn teeth on ring gear and/or
pinion.4. Replace ring gear and pinion.
5. Loose pinion bearings. 5. Adjust pinion bearing pre-load.
6. Loose differential bearings. 6. Adjust differential bearing pre-load.
7. Mis-aligned or sprung ring gear. 7. Measure ring gear run-out. Replace
components as necessary.
8. Loose differential bearing cap
bolts.8. Inspect differential components and
replace as necessary. Ensure that the
bearing caps are torqued tot he
proper specification.
9. Housing not machined properly. 9. Replace housing.
REMOVAL
(1) Raise and support the vehicle.
(2) Position a lifting device under axle and secure
lift to the axle.
(3) Remove wheels and tires assemblies.
(4) Remove all brake components.
(5) Mark propeller shaft and companion flange for
installation alignment reference.
(6) Remove propeller shaft.
(7) Remove shock absorbers from axle (Fig. 1).
(8) Remove U-bolts from axle (Fig. 2).(9) Remove axle from the vehicle.
Fig. 1 SHOCK ABSORBER
1 - NUT
2 - AXLE
3 - SHOCK ABSORBER
Fig. 2 REAR SPRING
1 - LEAF SPRING
2 - PLATE
3 - NUTS
4 - FRONT NUT & BOLT
5 - SPRING CLAMP BOLTS
6 - SHACKLES
DRREAR AXLE - 11 1/2 AA 3 - 143
REAR AXLE - 11 1/2 AA (Continued)