(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)
(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
LOW SPEED KNOCK
Low speed knock is generally caused by:
²Worn U-joint.
²Worn side gear thrust washers.
²Worn pinion shaft bore.
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.
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 - 9 1/4 3 - 81
REAR AXLE - 9 1/4 (Continued)
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)
(4) Place Arbor Disc 8541 on Arbor D-115-3 in posi-
tion in the housing side bearing cradles (Fig. 7).
Install differential bearing caps on arbor discs and
tighten cap bolts to 41 N´m (30 ft. lbs.).
NOTE: Arbor Discs 8541 has different step diame-
ters to fit other axles. Choose proper step for axle
being serviced.
(5) Assemble Dial Indicator C-3339 into Scooter
Block D-115-2 and secure set screw.
(6) Place Scooter Block/Dial Indicator in position
in axle housing so dial probe and scooter block are
flush against the rearward surface of the pinion
height block (Fig. 5). Hold scooter block in place and
zero the dial indicator. Tighten dial indicator face
lock screw.
(7) Slide the dial indicator probe across the gap
between the pinion height block and the arbor bar
with the scooter block against the pinion height block
(Fig. 8). Continue moving the dial probe to the crest
of the arbor bar and record the highest reading.
(8) Select a shim equal to the dial indicator read-
ing plus the drive pinion gear depth variance number
marked on the shaft of the pinion. For example, if
the depth variance is ±2, add +0.002 in. to the dial
indicator reading.
DIFFERENTIAL BEARING PRELOAD AND GEAR
BACKLASH
The following must be considered when adjusting
bearing preload and gear backlash:
²The maximum ring gear backlash variation is
0.076 mm (0.003 in.).
²Mark the gears so the same teeth are meshed
during all backlash measurements.
²Maintain the torque while adjusting the bearing
preload and ring gear backlash.
²Excessive adjuster torque will introduce a high
bearing load and cause premature bearing failure.
Insufficient adjuster torque can result in excessive
differential case free-play and ring gear noise.
²Insufficient adjuster torque will not support the
ring gear correctly and can cause excessive differen-
tial case free-play and ring gear noise.
NOTE: The differential bearing cups will not always
immediately follow the threaded adjusters as they
are moved during adjustment. To ensure accurate
bearing cup responses to the adjustments:
²Maintain the gear teeth engaged (meshed) as
marked.
²The bearings must be seated by rapidly rotat-
ing the pinion gear a half turn back and forth.
²Do this five to ten times each time the threaded
adjusters are adjusted.
Fig. 7 PINION DEPTH TOOLS
1 - ARBOR DISC
2 - PINION BLOCK
3 - ARBOR
4 - PINION HEIGHT BLOCK
Fig. 8 PINION GEAR DEPTH MEASUREMENT
1 - ARBOR
2 - SCOOTER BLOCK
3 - DIAL INDICATOR
3 - 86 REAR AXLE-91/4DR
REAR AXLE - 9 1/4 (Continued)
SIDE GEAR CLEARANCE
When measuring side gear clearance, check each
gear independently. If it necessary to replace a side
gear, replace both gears as a matched set.
(1) Install the axle shafts and C-locks and pinion
mate shaft.
(2) Measure each side gear clearance. Insert a
matched pair of feeler gauge blades between the gear
and differential housing on opposite sides of the hub
(Fig. 17).(3) If side gear clearances is no more than 0.005
inch. Determine if the axle shaft is contacting the
pinion mate shaft.Do not remove the feeler
gauges, inspect the axle shaft with the feeler
gauge inserted behind the side gear.If the end of
the axle shaft is not contacting the pinion mate
shaft, the side gear clearance is acceptable.
(4) If clearance is more than 0.005 inch (axle shaft
not contacting mate shaft), record the side gear clear-
ance. Remove the thrust washer and measure its
thickness with a micrometer. Add the washer thick-
ness to the recorded side gear clearance. The sum of
gear clearance and washer thickness will determine
required thickness of replacement thrust washer
(Fig. 18).
In some cases, the end of the axle shaft will move
and contact the mate shaft when the feeler gauge is
inserted. The C-lock is preventing the side gear from
sliding on the axle shaft.
(5) If there is no side gear clearance, remove the
C-lock from the axle shaft. Use a micrometer to mea-
sure the thrust washer thickness. Record the thick-
ness and re-install the thrust washer. Assemble the
differential case without the C-lock installed and re-
measure the side gear clearance.
(6) Compare both clearance measurements. If the
difference is less than 0.012 inch (0.305 mm), add
clearance recorded when the C-lock was installed to
thrust washer thickness measured. The sum will
determine the required thickness of the replacement
thrust washer.
(7) If clearance is 0.012 inch (0.305 mm) or
greater, both side gears must be replaced (matched
set) and the clearance measurements repeated.
(8) If clearance (above) continues to be 0.012 inch
(0.305 mm) or greater, the case must be replaced.
Fig. 16 HIGH PINION HEIGHT
Fig. 17 SIDE GEAR CLEARANCE
1 - FEELER GAUGE
2 - SIDE GEAR
Fig. 18 SIDE GEAR CALCULATIONS
DRREAR AXLE - 9 1/4 3 - 89
REAR AXLE - 9 1/4 (Continued)
SPECIFICATIONS
AXLE SPECIFICATIONS
DESCRIPTION SPECIFICATION
Axle Ratio 3.21, 3.55, 3.92
Differential Case Flange Runout 0.076 mm (0.003 in.)
Differential Case Clearance 0.12 mm (0.005 in.)
Ring Gear Diameter 235 mm (9.25 in.)
Ring Gear Backlash 0.12-0.20 mm (0.005-0.008 in.)
Ring Gear Runout 0.12 mm (0.005 in.)
Pinion Bearing Preload - New Bearings 1.7-4 N´m (15-35 in. lbs.)
Pinion Bearing Preload - Original Bearings 1-2 N´m (10-20 in. lbs.)
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Differential Cover Bolts 41 30 -
Bearing Cap Bolts 136 100 -
Ring Gear Bolts 157 115 -
Pinion Nut Minimum 285 210 -
Adjuster Lock Screw 10 7.5 90
Backing Plate Bolts 65 48 -
Pinion Mate Shaft Lock
Screw11 8 -
Axle U-Bolt Nuts 149 110 -
SPECIAL TOOLS
PULLER C-293-PA
PLUG C-293-3
ADAPTERS C-293-37
ADAPTERS C-293-47
3 - 90 REAR AXLE-91/4DR
REAR AXLE - 9 1/4 (Continued)