REMOVAL
(1) Raise and support vehicle.
(2) Remove wheel and tire assemblies.
(3) Remove half shaft hub nuts.
(4) Remove lower control arms. Refer to 2 suspen-
sion for procedure.
(5) Remove half shafts.
(6) Remove skid plate.
(7) Remove differential drain plug (Fig. 3) and
drain fluid.
(8) Remove differential vent hose (Fig. 4) from
cover.
(9) Remove propeller shaft from pinion flange.
(10) Support axle with a lift/jack.
(11) Remove bolt from left front axle bracket frame
mount (Fig. 5).
(12) Remove bolts from right axle bracket frame
mounts (Fig. 6).
(13) Remove bolt from left rear axle bracket frame
mount (Fig. 7).
(14) Lower axle from vehicle.
(15) Remove brackets from axle if necessary.
INSTALLATION
(1) Install left rear bracket to axle and tighten to
61 N´m (45 ft. lbs.).
(2) Install right bracket to axle and tighten to 88
N´m (65 ft. lbs.).(3) Install left front bracket to axle and tighten to
61 N´m (45 ft. lbs.).
(4) Raise axle up and align brackets with frame
mounts.
(5) Install frame mount bolts and tighten to 88
N´m (65 ft. lbs.).
(6) Install propeller shaft.
(7) Install half shafts.
Fig. 3 DRAIN PLUG
1 - LEFT FRONT AXLE BRACKET
2 - DRAIN PLUG
3 - DIFFERENTIAL HOUSING
Fig. 4 DIFFERENTIAL COVER
1 - COVER
2 - VENT TUBE
Fig. 5 LEFT FRONT AXLE BRACKET
1 - LEFT FRONT AXLE BRACKET
2 - BRACKET BOLT
3 - 24 FRONT AXLE - 186FIAKJ
FRONT AXLE - 186FIA (Continued)
Condition Possible Causes Correction
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.
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.
KJREAR AXLE - 198RBI 3 - 53
REAR AXLE - 198RBI (Continued)
(6) Install the bearing caps in their original loca-
tions (Fig. 50).
(7) Loosely install differential bearing cap bolts.
(8) Remove axle housing spreader.
(9) Tighten the bearing cap bolts to 64-91 N´m
(47-67 ft. lbs.).
(10) Install the axle shafts.
(11) Apply a 6.35mm (1/4 in.) bead of red Mopar
Silicone Rubber Sealant or equivalent to the housing
cover (Fig. 51).
CAUTION: If cover is not installed within 3 to 5 min-
utes, the cover must be cleaned and new RTV
applied or adhesion quality will be compromised.
(12) Install the cover and tighten cover bolts in a
criss-cross pattern to 38-45 N´m (28-33 ft. lbs.).
(13) Refill the differential with lubricant and
install fill plug.
(14) Remove support and lower the vehicle.
DIFFERENTIAL - TRAC-LOK
DIAGNOSIS AND TESTING - TRAC-LOKT
The most common problem is a chatter noise when
turning corners. Before removing the unit for repair,
drain, flush and refill the axle with the specified
lubricant. A container of Mopar Trac-loktLubricant
(friction modifier) should be added after repair ser-
vice 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.
(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. 52).
(6) If rotating torque is less than 41 N´m (56 ft.
lbs.) or more than 271 N´m (200 ft. lbs.) on either
wheel the unit should be serviced.
Fig. 50 BEARING CAP REFERENCE
1 - REFERENCE LETTERS
2 - REFERENCE LETTERS
Fig. 51 DIFFERENTIAL COVER - TYPICAL
1 - SEALING SURFACE
2 - SEALANT BEAD
3 - SEALANT THICKNESS
3 - 74 REAR AXLE - 198RBIKJ
DIFFERENTIAL (Continued)
Condition Possible Causes Correction
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.
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.
3 - 90 REAR AXLE-81/4KJ
REAR AXLE - 8 1/4 (Continued)
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, it indicates a binding
condition.
(9) The seal replacement is unacceptable if the
final pinion nut torque is less than 285 N´m (210 ft.
lbs.).
(10) Install the propeller shaft with the installa-
tion reference marks aligned.
(11) Install the brake drums.
(12) Check the differential housing lubricant level.
(13) Install wheel and tire assemblies and lower
the vehicle.
DIFFERENTIAL
REMOVAL
(1) Raise and support vehicle.
(2) Remove fill hole plug from the differential
housing cover.
(3) Remove differential housing cover and drain
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.
NOTE: Side play resulting from bearing races being
loose on case hubs requires replacement of the dif-
ferential case.
(6) Mark the differential housing and bearing caps
for installation reference (Fig. 28).
(7) Remove bearing threaded adjuster locks from
each bearing cap.
(8) Loosen bearing cap bolts, them loosen the
threaded adjusters with Wrench C-4164 (Fig. 29).
Fig. 27 Pinion Rotation Torque
1 - PINION YOKE
2 - INCH POUND TORQUE WRENCH
Fig. 28 Reference Mark
1 - REFERENCE MARKS
2 - REFERENCE MARKS
3 - DIFFERENTIAL HOUSING
4 - BEARING CAP
Fig. 29 Threaded Adjuster
1 - AXLE TUBE
2 - BACKING PLATE
3 - THREAD ADJUSTER WRENCH
3 - 104 REAR AXLE-81/4KJ
PINION SEAL (Continued)
(6) Install adjuster locks on the bearing caps.
(7) Install axle shafts.
(8) Apply a bead of red Mopar silicone rubber axle
sealant or equivalent to the housing cover (Fig. 33).
CAUTION: If cover is not installed within 3 to 5 min-
utes, the cover must be cleaned and new RTV
applied or adhesion quality will be compromised.
(9) Install cover and tighten bolts in a criss-cross
pattern to 41 N´m (30 ft. lbs.).
(10) Fill differential with gear lubricant to bottom
of the fill plug hole.
(11) Install the fill hole plug.
(12) Install wheel and tire assemblies.
(13) Remove support and lower vehicle.
(14) Trac-loktdifferential 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-LOKT
The most common problem is a chatter noise when
turning corners. Before removing the unit for repair,
drain, flush and refill the axle with the specified
lubricant. A container of Mopar Trac-loktLubricant
(friction modifier) should be added after repair ser-
vice 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.
(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. 34).
(6) If rotating torque is less than 41 N´m (56 ft.
lbs.) or more than 271 N´m (200 ft. lbs.) on either
wheel the unit should be serviced.
Fig. 33 Differential Cover Sealant
1 - SEALANT
2 - DIFFERNTIAL COVER
Fig. 34 ROTATING TORQUE TEST
1 - SPECIAL TOOL WITH BOLT IN CENTER HOLE
2 - TORQUE WRENCH
3 - 106 REAR AXLE-81/4KJ
DIFFERENTIAL (Continued)
OPERATION - REAR DRUM BRAKE
When the brake pedal is depressed hydraulic pres-
sure pushes the rear brake wheel cylinder pistons
outward. The wheel cylinder push rods then push the
brake shoes outward against the brake drum. When
the brake pedal is released return springs attached
to the brake shoes pull the shoes back to there orig-
inal position (Fig. 9).
REMOVAL
REMOVAL - FRONT BRAKE PADS
(1) Raise and support the vehicle.
(2) Remove the front wheel and tire assembly.
(3) Drain a small amount of fluid from the master
cylinder brake reservoir with acleansuction gun.(4) Bottom the caliper pistons into the caliper by
prying the caliper over.
(5) Remove the caliper mounting bolts.
(6) Remove the disc brake caliper from the mount.
CAUTION: Never allow the disc brake caliper to
hang from the brake hose. Damage to the brake
hose will result. Provide a suitable support to hang
the caliper securely.
(7) Remove the inboard and outboard pads.
REMOVAL - DRUM BRAKE SHOES
(1) Raise the vehicle and remove the rear wheels.
(2) Remove and discard the spring nuts securing
drums to wheel studs.
(3) Remove the brake drums. If drums prove diffi-
cult to remove, retract brake shoes. Remove the
access hole plug at the rear of backing plate and
back off adjuster screw with brake tool and screw-
driver.
(4) Clean the individual brake components, includ-
ing the support plate and wheel cylinder exterior,
with a find mist of water. Then wipe the brake com-
ponents clean with a dampened cloth.
(5) Remove the primary and secondary return
springs from anchor pin with the brake spring pliers.
(6) Remove the U-clip and washer securing
adjuster cable to the parking brake lever.
(7) Remove the hold-down springs, retainers and
pins with standard retaining spring tool.
(8) Remove the parking brake strut and cable
guide.
(9) Remove the adjuster lever, adjuster screw and
spring.
(10) Remove the adjuster cable.
(11) Remove the brake shoes.
(12) Disconnect the cable from the parking brake
lever and remove the lever ( if needed).
INSTALLATION
INSTALLATION - FRONT BRAKE PADS
(1) Install the inboard and outboard pads.
(2) Install the caliper (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DISC BRAKE CALIPERS
- INSTALLATION).
(3) Install the tire and wheel assembly. (Refer to
22 - TIRES/WHEELS/WHEELS - STANDARD PRO-
CEDURE).
INSTALLATION - DRUM BRAKE SHOES
Bonded linings should be replaced when worn to a
thickness of 1.6 mm (1/16 in.).
Fig. 9 BRAKE COMPONENTS
1 - SECONDARY SHOE
2 - SHOE GUIDE PLATE
3 - PRIMARY SHOE
4 - HORSE SHOE RETAINING CLIP
5 - PRIMARY RETURN SPRING
6 - PARK BRAKE STRUT
7 - HOLD DOWN SPRING AND RETAINERS
8 - SHOE RETURN SPRING
9 - ADJUSTER SCREW ASSEMBLY
10 - ADJUSTER LEVER
11 - ADJUSTER CABLE
12 - SECONDARY RETURN SPRING
13 - CABLE GUIDE
14 - WHEEL CYLINDER
15 - PARK BRAKE STRUT AND SPRING
16 - SUPPORT PLATE
KJBRAKES - BASE 5 - 11
BRAKE PADS / SHOES (Continued)
OPERATION
When the brakes are applied fluid pressure is
exerted against the caliper piston. The fluid pressure
is exerted equally and in all directions. This means
pressure exerted against the caliper piston and
within the caliper bore will be equal (Fig. 14).
Fluid pressure applied to the piston is transmitted
directly to the inboard brake shoe. This forces the
shoe lining against the inner surface of the disc
brake rotor. At the same time, fluid pressure within
the piston bore forces the caliper to slide inward on
the mounting bolts. This action brings the outboard
brake shoe lining into contact with the outer surface
of the disc brake rotor.
In summary, fluid pressure acting simultaneously
on both piston and caliper, produces a strong clamp-
ing action. When sufficient force is applied, friction
will attempt to stop the rotors from turning and
bring the vehicle to a stop.
Application and release of the brake pedal gener-
ates only a very slight movement of the caliper and
piston. Upon release of the pedal, the caliper and pis-
ton return to a rest position. The brake shoes do not
retract an appreciable distance from the rotor. In
fact, clearance is usually at, or close to zero. The rea-
sons for this are to keep road debris from gettingbetween the rotor and lining and in wiping the rotor
surface clear each revolution.
The caliper piston seal controls the amount of pis-
ton extension needed to compensate for normal lining
wear.
During brake application, the seal is deflected out-
ward by fluid pressure and piston movement (Fig.
15). When the brakes (and fluid pressure) are
released, the seal relaxes and retracts the piston.
The amount of piston retraction is determined by
the amount of seal deflection. Generally the amount
is just enough to maintain contact between the pis-
ton and inboard brake shoe.
REMOVAL
(1) Install prop rod on the brake pedal to keep
pressure on the brake system.
(2) Raise and support vehicle.
(3) Remove front wheel and tire assembly.
(4) Drain small amount of fluid from master cylin-
der brake reservoir with suction gun.
(5) Remove the brake hose banjo bolt if replacing
caliper (Fig. 16).
(6) Remove the caliper mounting slide pin bolts
(Fig. 16).
(7) Remove the caliper from vehicle.
DISASSEMBLY
(1) Remove brake shoes from caliper.
(2) Drain brake fluid out of caliper.
(3) Take a piece of wood and pad it with one-inch
thickness of shop towels. Place this piece in the out-
board shoe side of the caliper in front of the piston.
This will cushion and protect caliper piston during
removal (Fig. 17).
Fig. 14 Brake Caliper Operation
1 - CALIPER
2 - PISTON
3 - PISTON BORE
4 - SEAL
5 - INBOARD SHOE
6 - OUTBOARD SHOE
Fig. 15 Lining Wear Compensation By Piston Seal
1 - PISTON
2 - CYLINDER BORE
3 - PISTON SEAL BRAKE PRESSURE OFF
4 - CALIPER HOUSING
5 - DUST BOOT
6 - PISTON SEAL BRAKE PRESSURE ON
5 - 14 BRAKES - BASEKJ
DISC BRAKE CALIPERS (Continued)