For 1990-2009 cars

Cause | Correction
--- | ---
Inspect for the proper transaxle and gear oil levels prior to performing system diagnosis. Refer to Transfer Case Fluid Replacement .
Loose propeller shaft mounting bolts | Tighten the bolts, as required. Refer to Propeller Shaft Replacement .
Worn propeller shaft constant velocity joints | Replace the propeller shaft assembly. Refer to Propeller Shaft Replacement .
Worn axle shaft constant velocity joints | Replace the constant velocity joints, as required.
Loose rear differential torque tube bracket or a damaged bracket bushing | Tighten the bracket bolts or replace the bracket, as required.
Worn bearing in the rear axle torque tube assembly | Replace the torque tube assembly.
Incorrect gear oil in the transfer case | Replace the gear oil. Refer to Adhesives, Fluids, Lubricants, and Sealers .
Bearing noise within the transfer case 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 internal components, as required.

Gear set whine noise within the transfer case Whine type noises 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 internal components, as required.

Contributing factors may include:

• | Incorrect backlash between the gear sets

• | Worn or damaged gear teeth

• | Transaxle assembly noise

• | Rear differential noise