DISASSEMBLY & ASSEMBLY
Except 1996 Models
See Figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17
- Move the transfer case shift lever into 2H and move the vehicle forward and rearward about 3 ft. to be sure the transfer case is in Neutral.
- Raise and safely support the vehicle on jackstands.
- Remove the front wheel(s).
- Remove the locking hub cap-to-housing bolts and the cap.
- Remove the brake caliper-to-steering knuckle bolts and support the caliper on a wire; do not allow the caliper to hang on the brake hose. Do not disconnect the brake hose.
- Remove the brake caliper support bracket from the steering knuckle.
- Using snapring pliers, remove the snapring and shims.
- Remove the drive clutch assembly, the inner cam and lockwasher.
- Using a hub nut wrench, loosen the hub nut.
- Pull the hub from the spindle.
- Remove the outer bearing from the hub.
- Using a prytool, pry the inner bearing lip seal out of the inboard side of the hub, then remove the inner bearing assembly with your fingers.
- Wash all parts in a cleaning solvent and dry with compressed air. Do NOT allow the bearings to spin while drying them with the compressed air.
Always replace the bearing and race as a matched set, if replacement bearings are needed.
Check the bearings for pitting or scoring. Also check for smooth rotation and lack of noise as follows:
- Once the bearings and bearing races, located in the hub assembly, have been cleaned of all old grease and build up, oil the bearings with regular, clean engine oil.
- Position each bearing, 1 at a time, in its respective bearing race. Provide slight inward pressure and turn the bearings.
- While pressing in and rotating the bearings, note how they turn in the bearing races. The bearings should turn smoothly and evenly.
- If the bearings turn irregularly or make noises while rotating, they must be replaced with new ones. Any time the bearings are replaced, the bearing races should also be replaced.
Special installation tools are necessary to assemble new bearing races into the hub assembly.
If necessary, remove the bearing races as follows:
- Place the hub assembly on a piece of clean cardboard with the outboard side facing down.
- Using a long, brass drift pin or punch, tap the outer bearing race out of the hub assembly. It will be necessary to work the punch around the bearing in a circular motion, otherwise the bearing race can become excessive cocked in the hub bore; this makes removal almost impossible. If this happens, simply tap on the opposite side of the bearing race until it has leveled out in the bore.
- After the outer bearing race is removed, flip the hub over and perform the same with the inner bearing race.
- If removing the disc from the hub, scribe matchmarks, remove the disc-to-hub bolts and separate the disc from the hub.
- Clean the flange surface of the hub, thread holes, the surface of the lockwasher and the splines of the axle shaft.
- If the rotor was removed from the hub unit, position the rotor on the hub so the matchmarks align. Install the hub-to-rotor bolts and tighten in a crisscross fashion to 68-83 ft. lbs. (92-113 Nm).
If new wheel bearings are to be installed, and the old bearing races were removed, install the new inner and outer bearing races as follows:
- Position the hub unit so the outer side faces down on a clean work surface (cardboard or wood surface to prevent damage to the hub case). Position the new inner bearing race in the hub bore and drive it in place with the Bearing Race Installer Tool J-36829 and Installer Tool Grip J-8092, or their equivalents. Tap the race into the hub housing until it is seated completely in the bore.
- Turn the hub unit over so the inner side faces down and position the new outer bearing race in the hub bore. Drive it into the hub housing with Bearing Race Installer Tool J-29015 and Tool Grip J-8092, or their equivalents, as with the inner bearing race.
- Pack the bearings with wheel bearing grease, then install the inner bearing and a new grease seal in the hub. Use the Oil Seal Installer Tool J-36830 and Grip J-8092, or their equivalents.
- Carefully position the hub and disc assembly on the spindle. Place 1 to 1 1 / 2 oz. of bearing grease in the hub and install the outer bearing and hub nut on the spindle.
When installing the hub nut, perform the following procedures:
- Install the nut on the front spindle threads by hand. Make sure the side of the hub nut with chamfers in the machine screw holes faces outward; the machine screws must sit flush and if the hub nut is installed wrong, they cannot do so.
- Tighten the hub nut to 22 ft. lbs. (29 Nm), then completely loosen the nut; this seats the bearings on the spindle.
- Use a spring gauge connected at 90 degrees to the uppermost wheel stud to measure preload.
- Tighten the hub nut until the spring gauge measures a bearing preload of 4.4-5.5 lbs. (2.0-2.5 kg) for a new bearing and a new oil seal, or 2.6-4.0 lbs. (1.2-1.8 kg) for a used bearing and a new oil seal.
- Install the lockwasher with the larger diameter of the tapered bore to the outer side of the vehicle. If the bolt holes in the lock plate do not align with the corresponding holes in the nut, reverse the lock plate. If the bolt holes are still out of alignment, turn in the nut just enough to obtain alignment and install the lock screw tightly, so its head is lower than the surface of the washer.
- Install the inner cam by aligning the keyway of the inner cam with the groove of the knuckle. If the cam is difficult to install, use tool No. J-38194 or equivalent and a plastic hammer to lightly tap the inner cam into place.
Select the proper shim:
- Lower the vehicle and support the lower control arm with a block of wood and a floor jack to place the axle in the normal horizontal position.
- Install the special adjusting tools (J-36836 and J-36835-2, or equivalents) onto the hub until it comes in contact with the lockwasher.
- Pull the axle out as far as possible and using a feeler gauge, measure the clearance t between the hub and the snapring groove on the axle shaft.
- If the clearance is larger than the snapring groove, selected shims must be installed so clearance t is 0.000-0.039 in. (0.0-0.1mm). Shims come in thicknesses of 0.0079 in. (0.2mm), 0.0118 in. (0.3mm), 0.0197 in. (0.5mm), and 0.0393 in. (1.0mm).
- Remove the adjusting tools.
- Install the drive clutch assembly.
Install the shims selected above by hand on the axle and use the following steps to install a new snapring.
- Install special tool J-36835-2 or equivalent onto the axle.
- Install the snapring on the tool.
- Install tool driver J-36835-1 or equivalent.
- Pull out the axle shaft by pulling tool J-36835-2 or equivalent. Install the snapring to the axle by pushing on tool J-36835-1.
- Remove tool driver J-36835-2 or equivalent from the axle and check the fit of the snapring.
- Install the housing assembly and cap. Tighten the locking hub cap bolts to 43 ft. lbs. (58 Nm).
- Install the front wheels.
- Lower the vehicle to the floor.
See Figures 18 and 19
- Move the transfer case shift lever into 2H and move the vehicle forward and rearward to be sure the front axle is not engaged.
- Apply the parking brake and block the rear wheels.
- Break the lug nuts on the front wheels loose-do not completely loosen the lug nuts at this time.
- Raise and safely support the front of the vehicle on jackstands.
- Remove the front wheels.
- Unbolt and remove the hub dust cap.
- Remove the brake caliper from its support bracket and support it with a wire hook. Do not disconnect the brake hose.
Remove the brake caliper support bracket from the steering knuckle.
- Use snapring pliers to remove the snapring from the end of the axle shaft. Remove the shim.
- Slide the hub flange assembly off the axle shaft.
- Remove the lockwasher retaining screws, then pull the lockwasher out of the hub assembly.
- Use a hub nut wrench (J-36827 or equivalent) to loosen and remove the hub nut.
- Carefully pull the hub from the spindle; do not drag the hub assembly bearings across the spindle threads. Hold the outer wheel bearing with your thumb during removal to prevent it from falling out of the hub.
- Matchmark the hub and rotor so they can be assembled in the same positions. Place the hub and rotor assembly in a padded vice, then remove the 6 hub-to-rotor bolts to separate the rotor from the hub. If equipped with ABS, unbolt the sensor ring from the inside of the rotor.
- Thoroughly clean, inspect, and repack the bearings with wheel bearing grease. Replace the bearings if they show signs of damage (such as: nicks, burrs, bent or dented cage, flat spots on the rollers, etc.).
- If the bearings are to be replaced, or if the bearing races shows signs of damage, use a hammer and a brass drift to carefully tap the outer and inner bearing races and oil seals from the hub.
- Clean the flange surface of the hub, thread holes, the surface of the lockwasher, and the splines of the axle shaft.
- Use bearing drivers (inner bearing race, J-36829; outer bearing race, J-36828 or their equivalents) to install new inner and outer bearing races.
- Pack the bearings and the hub cavity with high-temperature wheel bearing grease.
- Install the rotor onto the hub and tighten the bolts to 76 ft. lbs. (103 Nm).
- If equipped, install the ABS sensor ring and tighten the bolts to 13 ft. lbs. (18 Nm).
- Install the inner bearing and the grease seal in the hub (use special tool J-36830 or equivalent). Position the hub and rotor assembly on the spindle.
- Install the outer bearing and spindle nut into the hub. Tighten the hub nut to 22 ft. lbs. (29 Nm) to seat the bearings and then fully loosen the nut. Use a spring scale connected to the stud bolt at a 90 degree angle to measure bearing preload. Then, retighten the hub nut until the spring gauge measures a bearing preload of 4.4-5.5 lbs. (19.6-24.5 N) for a new bearing and grease seal, or 2.6-4.0 lbs. (11.8-17.7 N) for a used bearing and a new grease seal.
- Install the lockwasher on the spindle nut. The larger diameter, tapered side of the lockwasher faces out, and the holes in the lockwasher must align with the holes in the spindle nut. If the holes don't align, reverse the washer or tighten the spindle just enough to bring them into alignment.
- Apply sealant to the both mating surfaces of the hub flange assembly and install it.
- Install the shim and the snapring. There should be 0.000-0.012 in. (0.0-0.3mm) of clearance between the hub body and the snapring. Shims of different thicknesses may be used, if necessary.
- Pack the hub dust cap with fresh grease and install it. Tighten the hub bolts to 43 ft. lbs. (59 Nm).
- Install the front wheels.
- Lower the vehicle.
- Verify that the front axle engages and the Shift-on-the-Fly 4WD system works correctly.