PINION GEAR DEPTH VARIANCE
Original Pinion
Gear Depth
VarianceReplacement Pinion Gear Depth Variance
24232221 0 +1 +2 +3 +4
+4+0.008 +0.007 +0.006 +0.005 +0.004 +0.003 +0.002 +0.001 0
+3+0.007 +0.006 +0.005 +0.004 +0.003 +0.002 +0.001 020.001
+2+0.006 +0.005 +0.004 +0.003 +0.002 +0.001 020.00120.002
+1+0.005 +0.004 +0.003 +0.002 +0.001 020.00120.00220.003
0+0.004 +0.003 +0.002 +0.001 020.00120.00220.00320.004
21+0.003 +0.002 +0.001 020.00120.00220.00320.00420.005
22+0.002 +0.001 020.00120.00220.00320.00420.00520.006
23+0.001 020.00120.00220.00320.00420.00520.00620.007
24020.00120.00220.00320.00420.00520.00620.00720.008
PINION DEPTH MEASUREMENT
Measurements are taken with pinion bearing cups
and pinion bearings installed in the housing. Take
measurements with Pinion Gauge Set and Dial Indi-
cator C-3339 (Fig. 5).(1) Assemble Pinion Height Block 6739, Pinion
Block 8542 and rear pinion bearing onto Screw 6741
(Fig. 5).
(2) Insert assembled height gauge components,
rear bearing, and screw into the housing through
pinion bearing cups (Fig. 6).
(3) Install front pinion bearing and Cone-Nut 6740
onto the screw. Tighten cone-nut until Torque To
Rotate the screw is 1.7 N´m (15 in. lbs.) (Fig. 5).
Fig. 5 PINION DEPTH GAUGE TOOLS
1 - DIAL INDICATOR
2 - ARBOR
3 - PINION HEIGHT BLOCK
4 - CONE
5 - SCREW
6 - PINION BLOCK
7 - SCOOTER BLOCK
8 - ARBOR DISC
Fig. 6 PINION HEIGHT BLOCK
1 - PINION BLOCK
2 - PINION HEIGHT BLOCK
DRREAR AXLE - 9 1/4 3 - 85
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)
(1) Through the axle tube use Wrench C-4164 to
adjust each threaded adjuster inward until the differ-
ential bearing free-play is eliminated. Allow some
ring gear backlash approximately 0.25 mm (0.01 in.)
between the ring and pinion gear. Seat the bearing
cups with the procedure described above.
(2) Install dial indicator and position the plunger
against the drive side of a ring gear tooth (Fig. 9).
Measure the backlash at 4 positions, 90 degrees
apart around the ring gear. Locate and mark the
area of minimum backlash.
(3) Rotate the ring gear to the position of the least
backlash. Mark the gear so that all future backlash
measurements will be taken with the same gear
teeth meshed.
(4) Loosen the right-side, tighten the left-side
threaded adjuster. Obtain backlash of 0.076 to 0.102
mm (0.003-0.004 in.) with each adjuster tightened to
14 N´m (10 ft. lbs.). Seat the bearing cups with the
procedure described above.
(5) Tighten the differential bearing cap bolts 136
N´m (100 ft. lbs.).
(6) Tighten the right-side threaded adjuster to 102
N´m (75 ft. lbs.). Seat the bearing cups with the pro-
cedure described above. Continue to tighten the
right-side adjuster and seat bearing cups until the
torque remains constant at 102 N´m (75 ft. lbs.)
(7) Measure the ring gear backlash. The range of
backlash is 0.15 to 0.203 mm (0.006 to 0.008 in.).(8) Continue increasing the torque at the right-
side threaded adjuster until the specified backlash is
obtained.
NOTE: The left-side threaded adjuster torque
should have approximately 102 N´m (75 ft. lbs.). If
the torque is considerably less, the complete
adjustment procedure must be repeated.
(9) Tighten the left-side threaded adjuster until
102 N´m (75 ft. lbs.) torque is indicated. Seat the
bearing rollers with the procedure described above.
Do this until the torque remains constant.
(10) Install the threaded adjuster locks and
tighten the lock screws to 10 N´m (90 in. lbs.).
GEAR 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 is correct (Fig. 10). Back-
lash and pinion depth is correct.
Fig. 9 RING GEAR BACKLASH
1 - DIAL INDICATOR
2 - RING GEAR
3 - EXCITER RING
Fig. 10 CORRECT CONTACT PATTERN
DRREAR AXLE - 9 1/4 3 - 87
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)
INSTALLER C-4308
INSTALLER C-4345
TRAC-LOK TOOLS C-4487
PULLER C-452
HANDLE C-4735
INSTALLER D-130
REMOVER 6310
HOLDER 6719A
PINION GAUGE SET 6730/6774/6775
TRAC-LOK TORQUE FIXTURE 6790
3 - 92 REAR AXLE-91/4DR
REAR AXLE - 9 1/4 (Continued)
(3) Install the axle shaft.
(4) Install differential cover and fill with gear
lubricant to the bottom of the fill plug hole.
AXLE BEARINGS
REMOVAL
(1) Remove axle shaft.
(2) Remove axle shaft seal from axle tube with a
small pry bar.
NOTE: The seal and bearing can be removed at the
same time with the bearing removal tool.
(3) Remove axle shaft bearing with Bearing
Remover 6310 and Foot 6310-9 (Fig. 24).
INSTALLATION
(1) Wipe the axle tube bore clean. Remove any old
sealer or burrs from the tube.
(2) Install axle shaft bearing with Installer C-4198
and Handle C-4171. Drive bearing in until tool con-
tacts the axle tube.
NOTE: Bearing is installed with the bearing part
number against the installer.(3) Coat the lip of thenewaxle seal with axle
lubricant and install with Installer C-4076-B and
Handle C-4735-1.
NOTE: When tool contacts the axle tube, the seal is
installed to the correct depth.
(4) Install the axle shaft.
(5) Install differential cover and fill with gear
lubricant to the bottom of the fill plug hole.
PINION SEAL
REMOVAL
(1) Mark universal joint, companion flange and
pinion shaft for installation reference.
(2) Remove propeller shaft from the companion
flange.
(3) Remove the brake rotors to prevent any drag.
(4) Rotate companion flange three or four times
and record pinion rotating torque with an inch pound
torque wrench.
(5) Install two bolts into the companion flange
threaded holes, 180É apart. Position Holder 6719A
against the companion flange and install and tighten
two bolts and washers into the remaining holes.
(6) Hold the companion flange with Holder 6719A
and remove pinion nut and washer.
(7) Remove companion flange with Remover C-452
(Fig. 25).
Fig. 24 AXLE SHAFT BEARING REMOVER
1 - AXLE SHAFT TUBE
2 - NUT
3 - GUIDE PLATE
4 - GUIDE
5 - THREADED ROD
6 - ADAPTER
7 - FOOT
Fig. 25 COMPANION FLANGE PULLER
1 - COMPANION FLANGE
2 - PULLER
DRREAR AXLE - 9 1/4 3 - 95
AXLE SHAFT SEALS (Continued)
(8) Remove pinion seal with pry tool or slide-ham-
mer mounted screw.
INSTALLATION
(1) Apply a light coating of gear lubricant on the
lip of pinion seal.
(2) Installnewpinion seal with Installer C-3860-A
and Handle C-4171 (Fig. 26)
(3) Install companion flange on the end of the
shaft with the reference marks aligned.
(4) Install two bolts into the threaded holes in the
companion flange, 180É apart.
(5) Position Holder 6719 against the companion
flange and install a bolt and washer into one of the
remaining threaded holes. Tighten the bolts so holder
is held to the flange.
(6) Install companion flange on pinion shaft with
Installer C-3718 and Holder 6719.
(7) Install pinion washer and anewpinion nut.
The convex side of the washer must face outward.
CAUTION: Never exceed the minimum tightening
torque 285 N´m (210 ft. lbs.) when installing the
companion flange retaining nut at this point. Dam-
age to collapsible spacer or bearings may result.
(8) Hold companion flange with Holder 6719 and
tighten the pinion nut with a torque set to 285 N´m
(210 ft. lbs.) (Fig. 27). Rotate pinion several revolu-
tions to ensure the bearing rollers are seated.
(9) Rotate pinion with an inch pound torque
wrench. Rotating torque should be equal to the read-
ing recorded during removal plus an additional 0.56
N´m (5 in. lbs.) (Fig. 28).CAUTION: Never loosen pinion nut to decrease pin-
ion bearing rotating torque and never exceed spec-
ified preload torque. If rotating torque is exceeded,
a new collapsible spacer must be installed.
Fig. 26 PINION SEAL INSTALLER
1 - HANDLE
2 - INSTALLER
3 - HOUSING
Fig. 27 TIGHTENING PINION NUT
1 - DIFFERENTIAL HOUSING
2 - COMPANION FLANGE HOLDER
3 - TORQUE WRENCH
Fig. 28 PINION ROTATION TORQUE
1 - COMPANION FLANGE
2 - TORQUE WRENCH
3 - 96 REAR AXLE-91/4DR
PINION SEAL (Continued)
(10) If rotating torque is low, use Holder 6719 to
hold the companion flange and tighten pinion nut in
6.8 N´m (5 ft. lbs.) increments until proper rotating
torque is achieved.
NOTE: The bearing rotating torque should be con-
stant during a complete revolution of the pinion. If
the rotating torque varies, this indicates a binding
condition.
NOTE: The seal replacement is unacceptable if the
final pinion nut torque is less than 285 N´m (210 ft.
lbs.).
(11) Install propeller shaft with the installation
reference marks aligned.
(12) Tighten the companion flange bolts to 108
N´m (80 ft. lbs.).
(13) Install brake rotors.
(14) Check the differential lubricant level.
DIFFERENTIAL COVER
REMOVAL
(1) With vehicle in neutral, position vehicle on
hoist.
(2) Remove drain plug.
(3) Remove cover bolts.
(4) Remove cover and drain lubricant.
INSTALLATION
(1) Apply a 6.35mm (1/4 in.) bead of Mopar Sili-
cone Rubber Sealant or equivalent to the housing
cover (Fig. 29).CAUTION: If housing cover is not installed within 3
to 5 minutes, the cover must be cleaned and new
RTV applied. Failure to heed caution may result in
damage.
(2) Install cover and identification tag. Tighten
cover bolts in a criss-cross pattern to 41 N´m (30 ft.
lbs.).
(3) Fill differential to specifications.
(4) Install fill plug.
DIFFERENTIAL
REMOVAL
(1) Remove filler plug from the differential cover.
(2) Remove differential cover and drain the lubri-
cant.
(3) Clean housing cavity with flushing oil, light
engine oil or a lint free cloth.
NOTE: Do not use steam, kerosene or gasoline to
clean the housing.
(4) Remove axle shafts.
(5) Remove RWAL/ABS sensor from housing.
NOTE: Side play resulting from bearing races being
loose on case hubs requires replacement of the dif-
ferential case.
(6) Mark differential housing and bearing caps for
installation reference (Fig. 30).
(7) Remove bearing threaded adjuster lock from
each bearing cap.
(8) Loosen differential bearing cap bolts.
Fig. 29 COVER SEALANT
1 - SEALANT
2 - DIFFERENTIAL COVER
Fig. 30 REFERENCE MARKS
1 - REFERENCE MARKS
2 - REFERENCE MARK
3 - BEARING CAPS
DRREAR AXLE - 9 1/4 3 - 97
PINION SEAL (Continued)