Cause  | Correction  | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Inspect for the proper transaxle and gear oil levels prior to performing system diagnosis. Refer to Transfer Case Fluid Replacement .  | |||||||||
Water or contamination within the lubricant Water or contamination within the lubricant, causing excessive torque converter clutch slip rate, may create a grind, growl, or moan in the rear differential or torque tube under light or steady load conditions.  | Replace the lubricant and flush the transfer case of the contaminated fluid. 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 propeller shaft assembly. Refer to Propeller Shaft Replacement .  | ||||||||
Worn axle shaft constant velocity joints  | Replace the constant velocity joints, as required.  | ||||||||
Loose rear axle torque tube bracket or a worn bracket bushing  | Tighten the bracket bolts or replace the bracket, as required.  | ||||||||
Worn bearing in the rear differential torque tube assembly  | Replace the torque tube assembly.  | ||||||||
Torque tube dampener loose or missing A moan or exhaust leak type noise at higher engine speeds, approximately 2,000-2,500 RPM, may indicate a loose or missing dampener.  | Tighten the dampener retaining bolt or replace the torque tube assembly, as required.  | ||||||||
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.  | 
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Gear set whine noise within the transfer case Whine type noises will increase or decrease relative to the vehicle speed.  | 
 Contributing factors may include: 
 
 
 
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