INSTALLATION
(1) Raise the axle with lifting device and align to
the leaf spring centering bolts.
(2) Install the spring clamps and spring brackets.
Refer to 2 Suspension for procedures.
(3) Install shock absorbers and tighten nuts to 82
N´m (60 ft. lbs.).
(4) Install the RWAL sensor to the differential
housing, if necessary. Refer to 5 Brakes for proce-
dures.
(5) Connect the parking brake cables and cable
brackets.
(6) Install the brake drums. Refer to 5 Brakes for
procedures.
(7) Connect the brake hose to the axle junction
block. Refer to 5 Brakes for procedures.
(8) Install axle vent hose.
(9) Align propeller shaft and pinion companion
flange reference marks. Install the companion flange
bolts. Tighten to 108 N´m (80 ft. lbs.).
(10) Install the wheels and tires.
(11) Add gear lubricant, if necessary. Refer to
Specifications for lubricant requirements.
(12) Remove lifting device from axle and lower the
vehicle.
ADJUSTMENTS
Ring gear and pinion are supplied as matched sets
only. The identifying numbers for the ring gear and
pinion are painted onto the pinion gear head (Fig. 6)
and the side of the ring gear. A plus (+) number,
minus (±) number or zero (0) along with the gear set
sequence number (01 to 99) is on each gear. This first
number is the amount (in thousandths of an inch)
the depth varies from the standard depth setting of a
pinion marked with a (0). The next two numbers are
the sequence number of the gear set. The standard
depth provides the best teeth contact pattern. Refer
to Backlash and Contact Pattern for additional infor-
mation.
Compensation for pinion depth variance is
achieved with select shims. The shims are placed
behind the rear pinion bearing. (Fig. 7).
If a new gear set is being installed, note the depth
variance painted onto both the original and replace-
ment pinion. Add or subtract the thickness of the
original depth shims to compensate for the difference
in the depth variances. Refer to the Depth Variance
chart.
Note where Old and New Pinion Marking columns
intersect. Intersecting figure represents plus or
minus the amount needed.Note the painted number on the shaft of the drive
pinion (±1, ±2, 0, +1, +2, etc.). The numbers repre-
sent thousands of an inch deviation from the stan-
dard. If the number is negative, add that value to the
required thickness of the depth shims. If the number
is positive, subtract that value from the thickness of
the depth shim. If the number is 0 no change is nec-
essary.
Fig. 6 Pinion ID Number
1 - PRODUCTION NUMBER
2 - PINION GEAR DEPTH VARIANCE
3 - GEAR MATCHING NUMBER
Fig. 7 Adjustment Shim Locations
1 - AXLE HOUSING
2 - COLLAPSIBLE SPACER
3 - PINION BEARING
4 - PINION DEPTH SHIM
5 - DRIVE PINION GEAR
6 - BEARING CUP
3 - 84 REAR AXLE-91/4BR/BE
REAR AXLE - 9 1/4 (Continued)
AXLE SHAFTS
REMOVAL
(1) Place the transmission in NEUTRAL and raise
and support vehicle.
(2) Remove wheel and tire assembly.
(3) Remove brake drum (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DRUM - REMOVAL) ..
(4) Clean all foreign material from housing cover
area.
(5) Remove the housing cover and drain lubricant.
(6) Rotate differential case to access the pinion
shaft lock screw. Remove lock screw and pinion shaft
from differential case (Fig. 17).
(7) Push axle shaft inward then remove axle shaft
C-lock (Fig. 18).
(8) Remove axle shaft being carefull not to damage
shaft bearing and seal.
(9) Inspect axle shaft seal for leakage or damage.
(10) Inspect axle shaft bearing contact surface for
signs of brinelling, galling and pitting.
INSTALLATION
(1) Lubricate bearing bore and seal lip with gear
lubricant. Insert axle shaft through seal, bearing and
engage it into side gear splines.
NOTE: Use care to prevent shaft splines from dam-
aging axle shaft seal lip.
(2) Insert C-lock in end of axle shaft. Push axle
shaft outward to seat C-lock in side gear.
(3) Insert pinion shaft into differential case and
through thrust washers and differential pinions.
(4) Align hole in shaft with hole in the differential
case and install lock screw with Loctiteton the
threads. Tighten lock screw to 11 N´m (8 ft. lbs.).
Trac-lok Tools 8139
Height Block 8542
Arbor Discs 8541
Fig. 17 Pinion Shaft Lock Screw
1 - LOCK SCREW
2 - PINION MATE SHAFT
Fig. 18 Axle Shaft C-Lock
1 - C-LOCK
2 - AXLE SHAFT
3 - SIDE GEAR
BR/BEREAR AXLE - 9 1/4 3 - 93
REAR AXLE - 9 1/4 (Continued)
(5) Install cover and fill with gear lubricant.
(6)
Install brake drum (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DRUM - INSTALLATION).
(7) Install wheel and tire assemblies.
(8) Remove support and lower vehicle.
AXLE SHAFT SEALS
REMOVAL
(1) Remove axle shaft.
(2) Remove axle shaft seal from the end of the axle
tube with a small pry bar (Fig. 19).
INSTALLATION
(1) Wipe the axle tube bore clean. Remove any old
sealer or burrs from the tube.
(2) Install anewaxle seal with Installer C-4076-B
and Handle C-4735-1. When the tool contacts the
axle tube, the seal is installed to the correct depth.
(3) Coat the lip of the seal with axle lubricant for
protection prior to installing the axle shaft.
(4) Install the axle shaft.
AXLE BEARINGS
REMOVAL
(1) Remove axle shaft.
(2) Remove axle shaft seal from the end of the axle
tube with a small pry bar (Fig. 20).
NOTE: The seal and bearing can be removed at the
same time with the bearing removal tool.(3) Remove the axle shaft bearing from the axle
tube with Bearing Removal 6310 and Adapter 6310-9
(Fig. 21).
Fig. 19 Axle Seal
1 - AXLE TUBE
2 - AXLE SEAL
3-PRYBAR
Fig. 20 Axle Seal
1 - AXLE TUBE
2 - AXLE SEAL
3-PRYBAR
Fig. 21 Axle Shaft Bearing
1 - NUT
2 - GUIDE PLATE
3 - GUIDE
4 - THREADED ROD
5 - ADAPTER
6 - FOOT
7 - AXLE TUBE
3 - 94 REAR AXLE-91/4BR/BE
AXLE SHAFTS (Continued)
INSTALLATION
(1) Wipe the axle tube bore clean. Remove any old
sealer or burrs from the tube.
(2) Install the axle shaft bearing with Installer
C-4198 and Handle C-4171 . Ensure that the bearing
part number is against the installer. Verify that the
bearing in installed straight and the tool fully con-
tacts the axle tube when seating the bearing.
(3) Install anewaxle seal with Installer C-4076-B
and Handle C-4735-1. When the tool contacts the
axle tube, the seal is installed to the correct depth.
(4) Coat the lip of the seal with axle lubricant for
protection prior to installing the axle shaft.
(5) Install the axle shaft.
PINION SEAL
REMOVAL
(1) Raise and support the vehicle.
(2) Mark the universal joint, companion flange and
pinion shaft for installation reference.
(3) Remove the propeller shaft from the companion
flange. Secure the propeller shaft in an upright posi-
tion to prevent damage to the rear universal joint.
(4) Remove the wheel and tire assemblies.
(5) Remove the brake drums to prevent any drag.
The drag may cause a false bearing preload torque
measurement.
(6) Rotate the companion flange three or four
times.
(7) Measure the amount of torque necessary to
rotate the pinion with an inch pound torque wrench.
Record the torque reading for installation reference.
(8) Install socket head bolts into two of the
threaded holes in the companion flange, 180É apart.
(9) Position Holder 6719A against the companion
flange and install a hex head bolt and washer into
one of the remaining threaded holes. Tighten the
bolts so the holder is held to the flange.
(10) Hold the flange with holder and remove the
pinion nut and washer.
(11) Remove the companion flange with Remover
C-452 (Fig. 22).
(12) Remove pinion seal with a pry tool or slide-
hammer mounted screw.
INSTALLATION
NOTE: The outer perimeter of the seal is pre-coated
with a special sealant. An additional application of
sealant is not required.
(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.NOTE: The seal is correctly installed when the seal
flange contacts the face of the differential housing.
(3) Position the companion flange on the end of the
shaft with the reference marks aligned.
(4) Install socket head bolts into two of the
threaded holes in the companion flange, 180É apart.
(5) Position Holder 6719A against the companion
flange and install a hex head bolt and washer into
one of the remaining threaded holes. Tighten the
bolts so the holder is held to the flange.
(6) Seat companion flange on pinion shaft with
Installer C-3718 and Holder 6719.
(7) Remove the installer and install the pinion
washer and anewpinion nut. The convex side of the
washer must face outward.
CAUTION: Do not exceed the minimum tightening
torque when installing the companion flange retain-
ing nut at this point. Damage to collapsible spacer
or bearings may result.
(8) Hold companion flange with Holder 6719 and
tighten the pinion nut to 285 N´m (210 ft. lbs.) (Fig.
23). Rotate pinion several revolutions to ensure the
bearing rollers are seated.
(9) Rotate the pinion using an (in. lbs.) 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. 24).
Fig. 22 Companion Flange Remover
1 - COMPANION FLANGE
2 - PULLER TOOL
BR/BEREAR AXLE - 9 1/4 3 - 95
AXLE BEARINGS (Continued)
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.(10) If the rotating torque is low, use Holder 6719
to hold the companion flange (Fig. 23) and tighten
the 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.
(11) The seal replacement is unacceptable if the
final pinion nut torque is less than 285 N´m (210 ft.
lbs.).
(12) Install the propeller shaft with the installa-
tion reference marks aligned.
(13) Tighten the companion flange bolts to 108
N´m (80 ft. lbs.).
(14) Install the brake drums.
(15) Install wheel and tire assemblies and lower
the vehicle.
(16) Check the differential housing lubricant level.
DIFFERENTIAL
REMOVAL
(1) Raise and support the vehicle.
(2) Remove lubricant fill hole plug from the differ-
ential housing cover.
(3) Remove differential housing cover and drain
the lubricant from the housing.
(4) Clean the housing cavity with a flushing oil,
light engine oil or lint free cloth.Do not use water,
steam, kerosene or gasoline for cleaning.
(5) Remove the axle shafts.
(6) 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.
(7) Mark the differential housing and differential
bearing caps for installation reference (Fig. 25).
(8) Remove bearing threaded adjuster lock from
each bearing cap. Loosen the bolts, but do not
remove the bearing caps.
(9) Loosen the threaded adjusters with Wrench
C-4164 (Fig. 26).
(10) Hold the differential case while removing
bearing caps and adjusters.
(11) Remove the differential case.
NOTE: Each differential bearing cup and threaded
adjuster must be kept with their respective bearing.
Fig. 23 Pinion Nut
1 - DIFFERENTIAL HOUSING
2 - COMPANION FLANGE HOLDER
3 - TORQUE WRENCH
Fig. 24 Pinion Rotation Torque
1 - COMPANION FLANGE
2 - INCH POUND TORQUE WRENCH
3 - 96 REAR AXLE-91/4BR/BE
PINION SEAL (Continued)
ASSEMBLY
(1) Install differential side gears and thrust wash-
ers.
(2) Install differential pinion and thrust washers.
(3) Install the pinion shaft.
(4) Align the hole in the pinion shaft with the hole
in the differential case and install the pinion shaft
lock screw.
(5) Lubricate all differential components with
hypoid gear lubricant.
INSTALLATION
(1) Apply a coating of hypoid gear lubricant to the
differential bearings, bearing cups, and threaded
adjusters. A dab of grease can be used to keep the
adjusters in position. Carefully position the assem-
bled differential case in the housing.
(2) Observe the reference marks and install the
differential bearing caps at their original locations
(Fig. 29).
(3) Install bearing cap bolts and tighten the upper
bolts to 14 N´m (10 ft. lbs.). Tighten the lower bolts
finger-tight until the bolt head is seated.
(4) Perform the differential bearing preload and
adjustment procedure.
NOTE: Be sure that all bearing cap bolts are tight-
ened to their final torque of 136 N´m (100 ft.lbs.)
before proceeding.
(5) Install the axle shafts.
(6) Apply a bead of Mopar Silicone Rubber Sealant
or equivalent to the housing cover (Fig. 30).Install the housing cover within 5 minutes
after applying the sealant.
(7) Install the cover and any identification tag.
Tighten the cover bolts to 41 N´m (30 ft. lbs.) torque.
(8) Fill differential with lubricant to bottom of the
fill plug hole. Refer to the Lubricant Specifications
for the quantity and type.
(9) Install the fill hole plug and lower the vehicle.
(10) Trac-lokydifferential equipped vehicles
should be road tested by making 10 to 12 slow figure-
eight turns. This maneuver will pump the lubricant
through the clutch discs to eliminate a possible chat-
ter noise complaint.
DIFFERENTIAL - TRAC-LOK
DIAGNOSIS AND TESTING - TRAC-LOKY
The most common problem is a chatter noise when
turning corners. Before removing a Trac-lokyunit
for repair, drain, flush and refill the axle with the
specified lubricant. A container of Mopar Trac-loky
Lubricant (friction modifier) should be added after
repair service or during a lubricant change.
After changing the lubricant, drive the vehicle and
make 10 to 12 slow, figure-eight turns. This maneu-
ver will pump lubricant through the clutches. This
will correct the condition in most instances. If the
chatter persists, clutch damage could have occurred.
DIFFERENTIAL TEST
The differential can be tested without removing the
differential case by measuring rotating torque. Make
sure brakes are not dragging during this measure-
ment.
(1) Place blocks in front and rear of both front
wheels.
Fig. 29 Bearing Caps & Bolts
1 - REFERENCE MARKS
2 - REFERENCE MARKS
3 - ADJUSTER LOCK
4 - BEARING CAP
Fig. 30 Differential Cover
1 - SEALANT
2 - DIFFERENTIAL COVER
3 - 98 REAR AXLE-91/4BR/BE
DIFFERENTIAL (Continued)
(2) Raise one rear wheel until it is completely off
the ground.
(3) Engine off, transmission in neutral, and park-
ing brake off.
(4) Remove wheel and bolt Special Tool 6790 or
equivalent tool to studs.
(5) Use torque wrench on special tool to rotate
wheel and read rotating torque (Fig. 31).
(6) If rotating torque is less than 22 N´m (30 ft.
lbs.) or more than 271 N´m (200 ft. lbs.) on either
wheel the unit should be serviced.
DISASSEMBLY
(1) Clamp side gear Holding Fixture 6965 in a vise
and position the differential case on the Holding Fix-
ture (Fig. 32).
(2) Remove ring gear if the ring gear is to be
replaced. The Trac-lokydifferential can be serviced
with the ring gear installed.
(3) Remove pinion shaft roll pin.
(4) Remove pinion shaft with a drift and hammer
(Fig. 33).
(5) Install and lubricate Step Plate C-6960-3 (Fig.
34).
(6) Assemble Threaded Adapter C-6960-1 into top
side gear. Thread Forcing Screw C-6960-4 into
adapter until it becomes centered in adapter plate.
Fig. 31 Trac-lokYTest -Typical
1 - SPECIAL TOOL 6790 WITH BOLT IN CENTER HOLE
2 - TORQUE WRENCH
Fig. 32 Differential Case Holding Fixture
1 - HOLDING FIXTURE
2 - VISE
3 - DIFFERENTIAL
Fig. 33 Pinion Shaft
1 - PINION MATE SHAFT
2 - SIDE GEAR
3 - DRIFT
4 - PINION MATE GEAR
BR/BEREAR AXLE - 9 1/4 3 - 99
DIFFERENTIAL - TRAC-LOK (Continued)
REAR AXLE - 248RBI
TABLE OF CONTENTS
page page
REAR AXLE - 248RBI
DESCRIPTION..........................109
OPERATION............................109
DIAGNOSIS AND TESTING.................111
AXLE...............................111
REMOVAL.............................113
INSTALLATION..........................114
ADJUSTMENTS.........................114
SPECIFICATIONS........................122
SPECIAL TOOLS........................122
AXLE SHAFTS
REMOVAL.............................125
INSTALLATION..........................125
AXLE BEARINGS
REMOVAL.............................125
INSTALLATION..........................125
PINION SEAL
REMOVAL.............................125INSTALLATION..........................125
DIFFERENTIAL
REMOVAL.............................127
DISASSEMBLY..........................128
ASSEMBLY............................128
INSTALLATION..........................129
DIFFERENTIAL - TRAC-LOK
DIAGNOSIS AND TESTING................130
TRAC-LOK...........................130
DISASSEMBLY..........................130
ASSEMBLY............................132
DIFFERENTIAL CASE BEARINGS
REMOVAL.............................134
INSTALLATION..........................134
PINION GEAR/RING GEAR/TONE RING
REMOVAL.............................135
INSTALLATION..........................137
REAR AXLE - 248RBI
DESCRIPTION
The Rear Beam-design Iron (RBI) axle housings
consist of an iron center casting (differential housing)
with axle shaft tubes extending from either side. The
tubes are pressed in to form a one-piece axle housing.
The integral type housing, hypoid gear design has
the centerline of the pinion set below the centerline
of the ring gear.
The axles are equipped with full-floating axle
shafts, meaning that loads are supported by the axle
housing tubes. The full-float axle shafts are retained
by bolts attached to the hub. The hub rides on two
bearings at the outboard end of the axle tube. The
axle shafts can be removed without disturbing or
removing the wheel bearings. The wheel bearings are
opposed tapered roller bearings and are contained in
the hub assembly.
The removable, stamped steel cover provides a
means for inspection and service without removing
the complete axle from the vehicle. A small, stamped
metal axle gear ratio identification tag is attached to
the housing cover via one of the cover bolts. This tag
also identifies the number of ring and pinion teeth.
The rear wheel anti-lock (RWAL) brake speed sen-
sor is attached to the top, forward exterior of the dif-
ferential housing. A seal is located between the
sensor and the wire harness connector. The seal mustbe in place when the wire connector is connected to
the sensor. The RWAL brake exciter ring is press-fit-
ted onto the differential case against the ring gear
flange.
The differential case for the standard differentials
and the Trac-lokydifferential are a one-piece design.
The differential pinion mate shaft is retained with a
roll pin. Differential bearing preload and ring gear
backlash are adjusted by the use of shims located
between the differential bearing cones and case. Pin-
ion bearing preload is set and maintained by the use
of a solid shims.
OPERATION
STANDARD DIFFERENTIAL
The axle receives power from the transmission/
transfer case through the rear propeller shaft. The
rear 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.
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
BR/BEREAR AXLE - 248RBI 3 - 109