REMOVAL & INSTALLATION
See Figures 1 and 2
This procedure disturbs the pinion bearing preload which must be reset for a correct repair. Do not attempt this procedure without a new pinion nut, inch pound torque wrench, rear axle universal joint flange holding tool and a pinion seal installation tool.
- Raise and safely support the vehicle.
- Place jackstands under the rear axle housing.
- Remove both wheel and tire assemblies.
- Remove the brake drums or calipers, as applicable.
- Mark the driveshaft and yoke for reassembly in the same location.
- Disconnect the driveshaft from the rear yoke.
- Place an inch pound (Nm) torque wrench with a suitable socket on the pinion nut. Record the torque required to maintain rotation of the pinion through several revolutions.
- Install Flange Holding Tool T78P-4851-A or equivalent on the rear axle universal joint flange. Remove the pinion nut while holding the flange stationary. Discard the pinion nut.
- Clean the area around the pinion seal. Place a suitable drain pan under the pinion seal.
- Mark the pinion shaft in relationship to the axle joint flange for assembly reference.
- Remove the rear axle joint flange using Companion Flange Remover T65L-4851-B or equivalent.
- Carefully place a suitable prytool under the flange of the pinion seal and strike with a hammer to wedge the prying tool between the seal and the axle housing. Pry on the flange of the pinion seal to raise the flange enough the grasp with suitable gripping pliers and remove the pinion seal.
- Clean the seal seating area in the axle housing.
- Before installing the new seal, coat the lip of the seal with a suitable wheel bearing grease, if not pre-greased.
- Place the pinion seal on Pinion Seal Installer T79P-4676-A or equivalent and install the pinion seal into the axle housing using a hammer.
- Check the axle universal joint flange for burrs and remove if found.
- Apply a small amount of rear axle lubricant to the rear axle universal joint flange splines.
- Align the index marks made on the axle universal joint flange and pinion shaft, then install the flange onto the shaft.
- Install Flange Holding Tool T78P-4851-A or equivalent, on the rear axle universal joint flange. Rotate the pinion shaft while tightening the pinion nut the ensure proper pinion bearing seating.
- Take frequent pinion bearing torque preload readings until the original recorded reading is reached. Tighten the nut in small increments to avoid overtightening.
- If the originally recorded pinion bearing preload is less than 8-14 inch lbs. (0.9-1.6 Nm) with original pinion bearing or 16-29 inch lbs. (1.8-3.2 Nm) with new pinion bearings, tighten the pinion nut to these readings.
Never back off the pinion nut to reduce pinion preload. If reduced preload is required, a new collapsible pinion spacer and pinion nut must be installed.
- Install the driveshaft, aligning the index marks made during disassembly.
- Add the proper rear axle lubricant to bring the level to approximately 1 / 2 in. (13mm) below the fill hole, if needed. Install the fill plug.
- Check the rear axle housing vent, making sure it is not plugged. A plugged vent can cause excessive pressure to build in the axle housing and leaking seals may result.
- Install the rear brake drums or calipers, as applicable.
- Install the wheel and tire assemblies. Tighten the lug nuts in a star pattern to 85-105 ft. lbs. (115-142 Nm).
- If the brake system was opened, bleed the rear brakes.
- Remove the jackstands, then carefully lower the vehicle.
- Road test the vehicle and check for leaks and proper operation.