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

Worn clutch disc and/or pressure plate assembly

Repair or replace, as required. Refer to Clutch Noisy .

Transmission noise

Repair or replace, as required. Refer to Transmission Noisy in Manual Transmission - Tremec 6-Speed or Diagnostic Starting Point - Automatic Transmission in Automatic Transmission - 6L80.

Driveline assembly noise

Repair or replace, as required. Refer to Symptoms - Propeller Shaft .

Worn axle shaft constant velocity joints

Replace the constant velocity joints, as required.

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 will increase or decrease 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 will increase or decrease relative to the vehicle speed, approximately 31-37 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.