Leaks

Most rear axle leakage conditions can be corrected without a teardown. However, it is important to clean the leaking area enough to identify the exact source of the leak.

A plugged or seized jiggle cap vent will cause excessive seal lip wear due to internal pressure buildup. When a leak occurs, inspect cap by pressing down on it with index finger. If the cap moves up and down freely, it is working properly. If it does not move freely, it must be replaced. Inspect axle lubricant level, which should be 9/16 inch below bottom of filler hole.

DRIVE PINION SEAL
If the drive pinion seal leaks, it is usually because of improper installation, or because of poor quality of the seal journal surface. Any damage to the seal bore, such as dings, dents and gouges, will distort the seal casing and allow leakage past the outer edge of the seal.

PINION NUT
Some models may experience oil leakage past the threads of the pinion nut. The condition can be corrected by removing the nut and applying pipe sealant with Teflon(R) D8AZ-19554-A, or equivalent, on the pinion threads and nut face. Ensure the proper procedure for setting the bearing preload is followed when the nut is installed.

POROUS CASTING
The differential carrier may leak through small pockets in the metal. These pockets (casting leakage) are caused by gas bubbles in the casting process.

Because the axle's sound characteristics may be changed if torn down to replace the carrier, servicing the porosity is preferable. Below are two recommended procedures that may be employed to fix a porous axle:
1. Peen a small amount of body lead into the hole, then seal the pocket with Epoxy Sealer Metallic Plastic C6A7-A9554-A, or equivalent.
2. In larger pockets, drill a shallow hole and tap it for a small setscrew. Install the setscrew and seal it over with Epoxy Sealer Metallic Plastic C6A7-A9554-A, or equivalent.


AXLE VENT
There have been some occurrences of lubricant leaking through the axle vent. This may be caused by a clogged or sticking axle vent cap. If this is the case, the vent assembly should be replaced. Use Stud and Bearing Mount part EOAZ-19554-BA, or equivalent, on vent's threads to ensure retention.