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 One-Piece Propeller Shaft Replacement or Two-Piece 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 the Transmission/Transaxle/Transfer Case 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 One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement in Propeller Shaft.
    • Replace the rear bushing if it is worn. Refer to Rear Output Shaft Seal Replacement .