
(8) Install lower control arms, refer to 2 Suspen-
sion for procedures.
(9) Install new half shaft hub nuts and tighten to
136 N´m (100 ft. lbs.).
(10) Install axle vent hose.
(11) Fill differential with gear lubricant.
(12) Install skid plate.
(13) Install wheel and tire assemblies.
(14) Remove support and lower vehicle.
(15) Check vehicle alignment.
ADJUSTMENTS
Ring and pinion gears are supplied as matched
sets only. The identifying numbers for the ring and
pinion gear are etched onto each gear (Fig. 8). A plus
(+) number, minus (±) number or zero (0) is etched
into the face of the pinion gear. This number is the
amount (in thousandths of an inch) the depth varies
from the standard depth setting of a pinion etched
with a (0). The standard setting from the center line
of the ring gear to the back face of the pinion is 92.1
mm (3.625 in.). The standard depth provides the best
gear tooth contact pattern. Refer to Backlash and
Contact Pattern Analysis paragraph in this section
for additional information.
Fig. 6 RIGHT AXLE BRACKET
1 - RIGHT AXLE BRACKET
2 - FRONT BRACKET BOLT
3 - REAR BRACKET BOLT
Fig. 7 LEFT REAR AXLE BRACKET
1 - LEFT REAR AXLE BRACKET
2 - BRACKET BOLT
Fig. 8 PINION GEAR ID NUMBERS
1 - PRODUCTION NUMBERS
2 - DRIVE PINION GEAR DEPTH VARIANCE
3 - GEAR MATCHING NUMBER
KJFRONT AXLE - 186FIA 3 - 25
FRONT AXLE - 186FIA (Continued)

INSTALLATION
(1) Install differential case bearings with Installer
C-3716-A and Handle C-4171 (Fig. 45).
(2) Install differential into the housing.
PINION GEAR/RING GEAR
REMOVAL
NOTE: The ring gear and pinion are serviced as a
matched set. Never replace ring gear without
replacing the matched pinion gear.
(1) Raise and support vehicle
(2) Mark pinion companion flange and propeller
shaft for installation alignment.
(3) Remove propeller shaft from pinion companion
flange and tie propeller shaft to underbody.
(4) Remove axle assembly from the vehicle.
(5) Remove differential from axle housing.
(6) Place differential case in a vise with soft metal
jaw (Fig. 46).
(7) Remove bolts holding ring gear to differential
case.
(8) Driver ring gear off the differential case with a
rawhide hammer (Fig. 46).(9) With Spanner Wrench 6958 and a short length
of 1 in. pipe, hold pinion companion flange and
remove pinion nut (Fig. 47).
Fig. 45 DIFFERENTIAL CASE BEARINGS
1 - HANDLE
2 - DIFFERENTIAL
3 - BEARING
4 - INSTALLER
Fig. 46 RING GEAR
1 - DIFFERENTIAL CASE
2 - RING GEAR
3 - HAMMER
Fig. 47 PINION COMPANION FLANGE
1 - SPANNER WRENCH
2 - PINION COMPANION FLANGE
3 - 44 FRONT AXLE - 186FIAKJ
DIFFERENTIAL CASE BEARINGS (Continued)

(10) Use Flange Wrench 6958, a length of 1 in.
pipe and a torque wrench set at 678 N´m (500 ft. lbs.)
and crush collapsible spacer until bearing end play is
taken up (Fig. 58).
(11) Slowly tighten the nut in 6.8 N´m (5 ft. lb.)
increments until the required rotating torque is
achieved. Measure the rotating torque frequently to
avoid over crushing the collapsible spacer (Fig. 59).
(12) Rotate the pinion a minimum of ten times.
Verify pinion rotates smoothly and check rotating
torque with an inch pound torque wrench (Fig. 59).
Pinion gear rotating torque is:
²Original Bearings: 1 to 2.25 N´m (10 to 20 in.
lbs.).
²New Bearings: 1.69 to 2.82 N´m (15 to 25 in.
lbs.).
(13) Invert the differential case and start two ring
gear bolts. This will provide case-to-ring gear bolt
hole alignment.
(14) Invert the differential case in the vise. Install
newring gear bolts and alternately tighten to 108
N´m (80 ft. lbs.) (Fig. 60).
CAUTION: Never reuse the ring gear bolts. The
bolts can fracture causing extensive damage.
(15) Install differential in housing and verify dif-
ferential bearing preload, gear mesh and contact pat-
tern. Refer to Adjustment for procedure.
(16) Install differential cover and fill with gear
lubricant.
(17) Install propeller shaft with reference marks
aligned.
(18) Remove supports and lower vehicle.
Fig. 58 PINION FLANGE NUT
1 - SPANNER WRENCH
2 - PINION COMPANION FLANGE
Fig. 59 PINION ROTATING TORQUE
1 - PINION COMPANION FLANGE
2 - TORQUE WRENCH
Fig. 60 RING GEAR BOLTS
1 - TORQUE WRENCH
2 - RING GEAR BOLTS
3 - RING GEAR
4 - DIFFERENTIAL CASE
3 - 48 FRONT AXLE - 186FIAKJ
PINION GEAR/RING GEAR (Continued)

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.
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.
3 - 52 REAR AXLE - 198RBIKJ
REAR AXLE - 198RBI (Continued)

(3) Position assembled clutch disc packs on the
side gear hubs.
(4) Install clutch pack and side gear in the ring
gear side of the differential case (Fig. 62).Verify
clutch pack retaining clips are in position and
seated in the case pockets.
(5) Position the differential case on the Holding
Fixture 6965.
(6) Install lubricated Step Plate 6960-3 in lower
side gear (Fig. 63).
(7) Install the upper side gear and clutch disc pack
(Fig. 63).
(8) Hold assembly in position. Insert Threaded
Adapter 6960-1 into top side gear.
(9) Install Forcing Screw 6960-4 and tighten screw
to slightly compress clutch disc.
(10) Place pinion gears in position in side gears
and verify that the pinion mate shaft hole is aligned.(11) Rotate case with Turning Bar 6960-2 until the
pinion mate shaft holes in pinion gears align with
holes in case. It may be necessary to slightly tighten
the forcing screw in order to install the pinion gears.
(12) Tighten forcing screw to 122 N´m (90 ft. lbs.)
maximum to compress the Belleville springs.
(13) Lubricate and install thrust washers behind
pinion gears and align washers with a small screw
driver. Insert mate shaft into each pinion gear to ver-
ify alignment.
(14) Remove Forcing Screw, Step Plate and
Threaded Adapter.
(15) Install pinion gear mate shaft and align holes
in shaft and case.
(16) Install pinion mate shaft lock screw finger
tight to hold shaft during differential installation.
(17) Lubricate all differential components with
hypoid gear lubricant.
Fig. 62 CLUTCH PACK AND LOWER SIDE GEAR
1 - DIFFERENTIAL CASE
2 - SIDE GEAR AND CLUTCH PACK
Fig. 63 CLUTCH PACK AND UPPER SIDE GEAR
1 - SIDE GEAR AND CLUTCH PACK
2 - DIFFERENTIAL CASE
3 - STEP PLATE
3 - 78 REAR AXLE - 198RBIKJ
DIFFERENTIAL - TRAC-LOK (Continued)

(15) Invert the differential case and start two ring
gear bolts. This will provide case-to-ring gear bolt
hole alignment.
(16) Invert the differential case in the vise.
(17) Installnewring gear bolts and alternately
tighten to 129-142 N´m (95-105 ft. lbs.) (Fig. 83).
CAUTION: Do not reuse the bolts that held the ring
gear to the differential case. The bolts can fracture
causing extensive damage.
(18) Install differential in housing.
(19) Verify differential bearing preload, gear mesh
and contact pattern. Refer to Ajustments for proce-
dure.
(20) Install differential cover and fill with gear
lubricant.
(21) Install the propeller shaft with the reference
marks aligned.
(22) Remove supports and lower vehicle.
Fig. 83 RING GEAR
1 - TORQUE WRENCH
2 - RING GEAR BOLT
3 - RING GEAR
4 - CASE
KJREAR AXLE - 198RBI 3 - 85
PINION GEAR/RING GEAR/TONE RING (Continued)

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.
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.
KJREAR AXLE - 8 1/4 3 - 89
REAR AXLE - 8 1/4 (Continued)

(16) Remove differential case from the fixture.
Remove side gear, clutch pack retainer and clutch
pack. Keep plates in order during removal.
CLEANING
Clean all components in cleaning solvent and dry
components with compressed air.
INSPECTION
Inspect clutch pack plates for wear, scoring or dam-
age. Replace both clutch packs if any one component
in either pack is damaged. Inspect side and pinion
gears for cracks chips or damage and replace as nec-
essary. Inspect differential case and pinion shaft and
replace if worn or damaged.
ASSEMBLY
Lubricate each component with gear lubricant
before assembly.
NOTE: New Plates and discs with fiber coating (no
grooves or lines) must be presoaked in Friction
Modifier before assembly. Soak plates and discs for
a minimum of 20 minutes.
(1) Assemble the clutch discs into packs and
secure disc packs with retaining clips (Fig. 42).
(2) Install assembled clutch disc packs on the side
gear hubs.(3) Install clutch pack and side gear in the ring
gear side of the differential case (Fig. 43).Verify
clutch pack retaining clips are in position and
seated in the case pockets.
(4) Set differential case on Fixture 8138.
(5) Install lubricated Disc 8140 without the hole in
lower side gear (Fig. 44).
(6) Install the upper side gear and clutch disc pack
(Fig. 44).
(7) Hold assembly in position. Insert Disc 8140
with threaded hole into top side gear.
(8) Install Forcing Screw 6960-4 and tighten screw
to slightly compress clutch disc.
(9) Place pinion gears in position in side gears and
verify that the pinion mate shaft hole is aligned.
(10) Rotate case with Turning Bar 6960-2 until the
pinion mate shaft holes in pinion gears align with
holes in case. It may be necessary to slightly tighten
the forcing screw in order to install the pinion gears.
(11) Tighten forcing screw to 122 N´m (90 ft. lbs.)
maximum to compress the Belleville springs.
(12) Lubricate and install thrust washers behind
pinion gears and align washers with a small screw
driver. Insert mate shaft into each pinion gear to ver-
ify alignment.
(13) Remove forcing screw and discs.
Fig. 42 CLUTCH DISC PACK
1 - CLUTCH PACK
2 - RETAINER
3 - SIDE GEAR
4 - RETAINER
Fig. 43 CLUTCH PACK AND LOWER SIDE GEAR
1 - DIFFERENTIAL CASE
2 - LOWER SIDE GEAR AND CLUTCH PACK
KJREAR AXLE - 8 1/4 3 - 109
DIFFERENTIAL - TRAC-LOK (Continued)