GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

DEFINITION: A noise heard in the rear axle during all driving conditions. This noise may increase or decrease in volume based on different driving maneuvers and speeds.

Flat spot on the pinion or the ring gear teeth

Replace the pinion and the ring gear. Refer to Drive Pinion and Ring Gear Replacement .

Flat spot on the pinion bearing

Replace the bearing. Refer to Drive Pinion Bearings Replacement .

Worn pinion splines

Replace the pinion. Refer to Drive Pinion and Ring Gear Replacement.

Low oil level

Fill the fluid level to specifications with the proper lubricant. Refer to Lubricant Level Check.

Wrong or poor grade oil

Drain and refill the system with the proper lubricant. Refer to Axle Lubricant Change.

Excessive pinion to ring gear backlash

Adjust the pinion to ring gear backlash. Refer to Backlash Adjustment.

Loose pinion bearings

Adjust the pinion bearings preload. Refer to Pinion Depth Adjustment.

Excessive pinion end play

Adjust the pinion end play. Refer to Pinion Depth Adjustment.

Incorrect differential bearing preload

Adjust the differential bearing preload. Refer to Differential Carrier Bearing Preload Adjustment.

Incorrect backlash

Adjust the pinion and ring gear backlash. Refer to Backlash Adjustment.

Worn pinion bearings

Replace the pinion bearings. Refer to Drive Pinion Bearings Replacement.

Worn differential bearings

Replace the differential bearings. Refer to Differential Side Bearings Replacement.

Worn pinion and ring gear

Replace the pinion and ring gear. Refer to Drive Pinion and Ring Gear Replacement.

Excessive ring gear runout

Replace the ring gear. Refer to Drive Pinion and Ring Gear Replacement.

Bent axle housing

Replace the axle housing. Refer to Rear Axle Housing Replacement.

Worn axle shaft dowel holes

Replace the axle shaft. Refer to Rear Axle Shaft Replacement or to Rear Axle Shaft and/or Gasket Replacement .

Worn hub studs

Replace the wheel studs. Refer to Wheel Stud Replacement.

Bent axle shaft

Replace the axle shaft. Refer to Rear Axle Shaft Replacement or Rear Axle Shaft and/or Gasket Replacement .