Lincoln YW1Z-4602-AA Drive Shaft Assembly

Raise the rear of the vehicle and support it securely on jackstands. Crawl under the vehicle and visually inspect the driveshaft for any dents or cracks in the tubing, if any are found, the driveshaft must be replaced. Check for any oil leakage at the front and rear of the driveshaft. Leakage where the driveshaft enters the transmission indicates a defective transmission rear seal, while leakage where the driveshaft enters the differential indicates a defective pinion seal. While under the vehicle, have an assistant turn a rear wheel so the driveshaft will rotate. As it does, make sure the universal joints are operating properly without binding, noise or looseness. The universal joints can also be checked with the driveshaft motionless, by gripping your hands on either side of the joint and attempting to twist the joint. Any movement at all in the joint is a sign of considerable wear. Lifting up on the shaft will also indicate movement in the universal joints. Finally, check the driveshaft mounting bolts at the ends to make sure they are tight.