Jeep Cherokee (XJ): 186 FBI pinion

The ring gear and pinion are serviced as a matched set. Do not replace the pinion without replacing the ring gear.

REMOVAL

(1) Remove differential assembly from axle housing.

(2) Mark pinion yoke and propeller shaft for installation alignment.

(3) Disconnect propeller shaft from pinion yoke.

Using suitable wire, tie propeller shaft to underbody.

(4) Using Holder 6958 to the hold yoke, remove the pinion nut and washer (Fig. 50).

(5) Using Remover C-452 and Holder C-3281, remove the pinion yoke from pinion shaft (Fig. 51).

Fig. 50 Pinion Yoke Holder-Typical

1 - 1 in. PIPE
2 - PINION YOKE
3 - SPECIAL TOOL 6958
4 - LOWER CONTROL ARM

Fig. 51 Pinion Yoke Removal

1 - SPECIAL TOOL C-3281
2 - YOKE
3 - SPECIAL TOOL C-452

(6) Remove the pinion and collapsible spacer from housing (Fig. 52). Catch the pinion with your hand to prevent it from falling and being damaged.

Fig. 52 Remove Pinion

1 - RAWHIDE HAMMER

(7) Remove the front pinion bearing cup, bearing, oil slinger, if equipped, and pinion seal with Remover C-4345 and Handle C-4171 (Fig. 53).

Fig. 53 Front Bearing Cup Removal

1 - REMOVER
2 - HANDLE

(8) Remove the rear pinion bearing cup from axle housing (Fig. 54). Use Remover D-149 and Handle C-4171.

Fig. 54 Rear Bearing Cup Removal

1 - DRIVER
2 - HANDLE

(9) Remove the collapsible preload spacer from pinion gear (Fig. 55).

Fig. 55 Collapsible Spacer

1 - COLLAPSIBLE SPACER
2 - SHOULDER
3 - PINION
4 - PINION DEPTH SHIM
5 - REAR BEARING

(10) Remove the rear pinion bearing from the pinion with Puller/Press C-293-PA and Adapters C-293-39 (Fig. 56).

Place 4 adapter blocks so they do not damage the bearing cage.

Fig. 56 Inner Bearing Removal

1 - SPECIAL TOOL C-293-PA
2 - VISE
3 - ADAPTERS
4 - DRIVE PINION GEAR SHAFT

(11) Remove the depth shim/oil slinger from the pinion shaft. Record the thickness of the depth shim/ oil slinger.

INSTALLATION

NOTE: A pinion depth shim/oil slinger is placed between the rear pinion bearing cone and the pinion head to achieve proper ring gear and pinion mesh. If the factory installed ring gear and pinion are reused, the pinion depth shim/oil slinger should not require replacement. Refer to Pinion Gear Depth to select the proper thickness shim/oil slinger before installing pinion.

(1) Apply Mopart Door Ease, or equivalent, stick lubricant to outside surface of rear pinion bearing cup. Install the bearing cup with Installer D-146 and Driver Handle C-4171 (Fig. 57). Verify cup is correctly seated.

(2) Apply Mopart Door Ease, or equivalent, stick lubricant to outside surface of front pinion bearing cup. Install the bearing cup with Installer D-130 and Handle C-4171 (Fig. 58).

Fig. 57 Rear Pinion Bearing Cup Installation

1 - INSTALLER
2 - HANDLE

Fig. 58 Pinion Outer Bearing Cup Installation

1 - INSTALLER
2 - HANDLE

(3) Install front pinion bearing, and oil slinger, if equipped.

(4) Apply a light coating of gear lubricant on the lip of pinion seal. Install seal with Installer C-3972-A and Handle C-4171 (Fig. 59).

(5) Install the rear pinion bearing and the pinion depth shim/oil slinger onto the pinion with Installer W-262 and a shop press (Fig. 60).

Fig. 59 Pinion Seal Installation

1 - SPECIAL TOOL C-4171
2 - SPECIAL TOOL C-3972-A

Fig. 60 Rear Pinion Bearing Installation

1 - PRESS
2 - INSTALLATION TOOL
3 - PINION DEPTH SHIM/OIL BAFFLE
4 - DRIVE PINION
5 - DRIVE PINION SHAFT REAR BEARING

(6) Install a new collapsible preload spacer on pinion shaft and install pinion in housing (Fig. 61).

(7) Install yoke with Installer W-162-B, Cup 8109, and Holder 6958 (Fig. 62).

(8) Install the pinion washer and a new nut onto the pinion. Tighten the nut to 216 N·m (160 ft. lbs.) minimum. Do not over-tighten. Maximum torque is 352 N·m (260 ft. lbs.).

CAUTION: Never loosen the pinion nut to decrease pinion bearing rotating torque and never exceed specified preload torque. If preload torque is exceeded a new collapsible spacer must be installed. The torque sequence will then have to be repeated.

Fig. 61 Collapsible Preload Spacer

1 - COLLAPSIBLE SPACER
2 - SHOULDER
3 - PINION GEAR
4 - OIL SLINGER
5 - REAR BEARING

Fig. 62 Pinion Yoke Installation

1 - PINION YOKE
2 - AXLE HOUSING

(9) Using Holder 6958 and torque wrench (set at 352 N·m (260 ft. lbs.)), crush collapsible spacer until bearing end play is taken up (Fig. 63). If more than 353 N·m (260 ft. lbs.) is needed to begin to collapse the spacer, the spacer is defective and must be replaced.

(10) Slowly tighten the nut in 6.8 N·m (5 ft. lb.) increments until the rotating torque is achieved.

Measure the rotating torque frequently to avoid over crushing the collapsible spacer (Fig. 64).

Fig. 63 Tightening Pinion Nut-Typical

1 - PINION FLANGE
2 - FRONT AXLE
3 - TOOL 6958

(11) Check bearing rotating torque with an inch pound torque wrench (Fig. 64). The torque necessary to rotate the pinion should be:

•  Original Bearings - 1 to 2 N·m (10 to 20 in. lbs.).
• New Bearings - 1.5 to 4 N·m (15 to 35 in. lbs.).

(12) Install differential assembly.