Rear Drive Axle and Differential

Analysis of Leakage

Clean up the leaking area enough to identify the exact source.

A plugged Rear axle housing vent can cause excessive pinion seal lip wear due to internal pressure buildup.

Verify the differential lubricant level is at the correct level. REFER to: Differential Fluid Level Check (205-02 Rear Drive Axle/Differential, General Procedures).

Axle Vent

A plugged vent will cause excessive seal lip wear due to internal pressure buildup. If a leak occurs, check the vent. If the vent cannot be cleared, install a new vent.

Drive Pinion Seal

Leaks at the drive pinion seal originate from the following causes:

Damaged seal Worn seal journal surface

A new drive pinion flange must be installed if any of these conditions exist.

Any damage to the seal bore (dings, dents, gouges or other imperfections) distorts the seal casing and allows leakage past the outer edge of the drive pinion seal. The drive pinion seal can be torn, cut or gouged if it is not installed correctly. The spring that holds the drive pinion seal against the pinion flange may be knocked out and allow fluid to pass the lip. Metal chips trapped at the sealing lip can cause oil leaks. These can cause a wear groove on the drive pinion flange and result in pinion seal wear. When a seal leak occurs, install a new drive pinion seal and check the vent to make sure it is clean and free of foreign material.

Differential Seals

Halfshaft pilot bearing housing seals are susceptible to the same types of damage as drive pinion seals if incorrectly installed. The seal bore must be clean and the lip handled carefully to avoid cutting or tearing it. The seal journal surface must be free of nicks, gouges and rough surface texture.

Contact Pattern

In general, desirable ring gear tooth patterns must have the following characteristics:

Drive pattern on the drive side ring gear well centered on the tooth. Coast pattern on the coast side ring gear well centered on the tooth. Clearance between the pattern and the top of the tooth. No hard lines where the pressure is high.

Acceptable ring gear tooth patterns for all axles.