REMOVAL & INSTALLATION
- Raise and safely support the rear of the truck as necessary. There is less chance of lubricant leakage from the rear of the transmission on two wheel drive models if the rear is raised.
- Matchmark the driveshaft and flanges on the rear axle and transfer case or transmission.
- Remove the U-bolts or straps at the axle end of the shaft. Tape the bearings into place to avoid losing them.
- If there are U-bolts or straps at the front end of the shaft, remove them. Tape the bearings into place. Compress the shaft slightly and remove it. All four wheel drive models are of this type.
- If there are no fasteners at the front end of the shaft, slide the shaft forward slightly to disengage the axle flange, then pull it back out of the transmission. Most two wheel drive models are of this type.
- Reverse the procedure for installation. On two wheel drive automatic transmission models, lubricate the internal yoke splines at the transmission end of the shaft with lithium base grease. The grease should seep out through the vent hole. On most 1975-80 four wheel drive models, the driveshaft can be installed either way, since both U-joints are the same size.
A thump in the rear driveshaft sometimes occurs when releasing the brakes after braking to a stop, especially on a downgrade. This is most common with automatic transmission. It is often caused by the driveshaft splines binding and can be cured by removing the driveshaft, inspecting the splines for rough spots or sharp edges, and carefully lubricating. A similar thump may be caused by the clutch plates in Positraction (1969-73) limited slip rear axles binding. If this isn't caused by wear, it can be cured by draining and refilling the rear axle with the special lubricant and adding Positraction additive, both of which are available from dealers.