Slip-Yoke Spline

Vehicle noise and vibration can be caused by a seized driveshaft slip yoke (4841) spline resulting in the rubber isolator being pulled out of the driveshaft center bearing bracket (4A499).

The service resolution to minimize driveshaft slip yoke spline contamination and ultimate seizure is as follows:

1. Disconnect the driveshaft (4602) from the rear axle yoke and remove it from the truck.

2. Clean the male splines of the coupling shaft using care not to damage the plastic coating. Fine abrasive cloth may be required to dress and polish the male spline. Remove all hardened grease deposits, dirt or rust. Inspect for worn or galled splines. The plastic coating on the stub spline must not be removed. Replace coupling shaft if necessary.

3. Clean and inspect the female splines of the driveshaft slip yoke, removing any hardened grease deposits, dirt or rust. Inspect splines for worn or galled conditions, replace driveshaft slip yoke if necessary.

4. Apply a coating of Premium Long-Life Grease XG-1-C or -K or equivalent meeting Ford specification ESA-M1C75-B to the entire splined stub end of the coupling shaft prior to the assembling of the driveshaft to the coupling shaft.

5. Using a clean, long handle (stencil-type) brush apply Premium Long-Life Grease XG-1-C or -K or equivalent meeting Ford specification ESA-M1C75-B spread evenly on all the female splines of the slip yoke. The spline joint must slide freely by hand.

6. Assemble the driveshaft to the coupling shaft with the yokes phased properly. Attach driveshaft to rear axle yoke.

7. Using a hand-type grease gun, lubricate the driveshaft slip yoke through the grease fitting with Premium Long-Life Grease XG-1-C or -K or equivalent meeting Ford specification ESA-M1C75-B.