GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2002 🢒 GMC C Sierra - 2WD 🢒 Driveline/Axle 🢒 Transfer Case - NVG 263-NP1 (Selectable) 🢒 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 and 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 Transfer Case - NVG 263-NP1 Unit Repair.

Excessive clearance between the slip yoke and the rear bushing
    • Inspect the rear bushing for visible signs of wear.
    • Inspect the slip yoke bushing 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 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 Transfer Case - NVG 263-NP1 Unit Repair.
    • Inspect for worn or missing input gear thrust washers. Refer to Transfer Case Cleaning and Inspection in Transfer Case - NVG 263-NP1 Unit Repair.