LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 1150 (Transfer Case - STEYR) >> Diagnostic Information and Procedures >> Noisy in Drive

Noisy in Drive

WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
Noisy in Drive

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 transmission oil
Water or contamination within the transmission fluid, 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 transmission fluid and flush the transfer case of the contaminated fluid. Refer to Internal Components Cleaning and Inspection in Transfer Case - Steyr Unit Repair.
Loose propeller shaft mounting bolts Tighten the bolts as required. Refer to Propeller Shaft Replacement in Propeller Shaft.
Worn propeller shaft constant velocity joints Replace propeller shaft assembly. Refer to Propeller Shaft Replacement in Propeller Shaft.
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 dampner 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 dampner.
Tighten the dampner retaining bolt or replace the torque tube assembly as required.
Incorrect gear oil in the transfer case Replace with gear oil GM P/N 12378514 (Canadian P/N 88901045).
Bearing noise within the transfer case
A "grinding" or "roar" type noise will increase or decrease relative to the vehicle speed.
  1. Check 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 approximately 80-97 km/h (50-60 mph).
  1. Check 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