Transfer Case Clunk in 2HI Only. GMC Truck Sonoma Pickup

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2002 🢒 Sonoma Pickup - 4WD 🢒 Driveline/Axle 🢒 Transfer Case - NVG 236/246-NP8 (Two Speed Automatic) 🢒 Transfer Case Clunk in 2HI Only

Cause

Correction

DEFINITION: During acceleration or deceleration a clunk is heard or felt in the transfer case.

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 required. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement in Propeller Shaft.

•	Replace the rear output shaft, if required. 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 required. 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 .

Worn high speed teeth on the range collar

•	Inspect for worn high speed teeth on the range collar. Refer to Transfer Case Cleaning and Inspection in the Transmission/Transaxle/Transfer Case Unit Repair Manual.

•	Inspect for worn or missing input gear thrust washers. Refer to Transfer Case Cleaning and Inspection in the Transmission/Transaxle/Transfer Case Unit Repair Manual.