Transfer Case Clunk during Acceleration and Deceleration

WARNING: This page is about a different car, the 2008 GMC Sierra and 2008 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

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. Inspect the transfer case for the correct type of fluid. Refer to Approximate Fluid Capacities . Flush the transfer case and fill with the correct fluid, if required. Refer to Transfer Case Fluid Replacement .
Excessive clearance between the slip yoke and the rear output shaft	Inspect for the following conditions: Worn slip yoke splines Worn rear output shaft splines Repair or replace the following components if faulty: Replace the slip yoke, if required. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement . Replace the rear output shaft, if required. Refer to Transfer Case Disassemble and Transfer Case Assemble .
Excessive clearance between the slip yoke and the rear bushing	Inspect for the following conditions: Worn rear bushing Worn slip yoke bushing journal Repair or replace the following components if faulty: Replace the slip yoke, if required. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement . Replace the rear bushing if worn. Refer to Transfer Case Rear Extension Bushing Replacement .