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.

Important: Inspect for the proper gear oil levels prior to performing system diagnosis. Refer to Rear Axle Lubricant Level Inspection .

Low gear oil levels

Faulty oil seals or other type leaks may contribute to lower than required fluid levels. Refer to Rear Axle Lubricant Leak Diagnosis .

Fill to the proper level with the correct gear oil and friction modifier additive. Refer to Adhesives, Fluids, Lubricants, and Sealers .

Worn, loose, or damaged axle mount and/or bracket

Repair or replace the axle mount and/or bracket, as required.

Bearing noise within the differential assembly

A grinding or roar type noise increases or decreases relative to the vehicle speed.

  1. Inspect for the proper fluid level. Fill, as required.
  2. If the noise continues, repair or replace the unit, as required.

Gear set whine noise within the differential assembly

A whine type noise increases or decreases relative to the vehicle speed, approximately 80-96 km/h (50-60 mph). Typical causes of a gear set whine type noise may include incorrect backlash and/or pinion depth adjustment or worn or scored gear set teeth.

  1. Inspect for the proper fluid level. Fill, as required.
  2. Repair or replace the unit, as required.