GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

DEFINITION: During acceleration or deceleration, a clunk is heard or felt in the transfer case when it is in AWD mode.

Review the Symptoms - Transfer Case and perform the necessary inspections.

Incorrect fluid level or incorrect fluid

    •  Inspect the transfer case for the correct fluid level. Refer to Transfer Case Fluid Replacement .
    • Fill the transfer case to the correct fluid level, if required.
    • Inspect the transfer case for the correct type of fluid.
    • Flush the transfer case, and fill with the correct fluid, if required.

Excessive clearance between the slip yoke and the rear output shaft

    • Inspect the slip yoke splines for wear.
    • Inspect the rear output shaft splines for wear.
    • Replace the slip yoke if it is faulty. Refer to Front Propeller Shaft Replacement or Rear Propeller Shaft Replacement in Propeller Shaft.
    • Replace the rear output shaft if it is faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transmission, Transaxle Unit Repair Manual.

Excessive clearance between the slip yoke and the rear bushing

    • Inspect the rear bushing for visible signs of wear.
    • Inspect the slip yoke bearing journal for wear.
    • Replace the slip yoke if it is faulty. Refer to Front Propeller Shaft Replacement or Rear Propeller Shaft Replacement in Propeller Shaft.
    • Replace the rear bushing if it is worn. Refer to Rear Output Shaft Seal Replacement .