GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

DEFINITION: A faulty internal transfer case component that causes a whine or rumble noise in the transfer case.

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

Faulty bearings

Inspect all bearings and journals. Replace any faulty bearings and any components with faulty bearing journals. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - NVG 226-NP8 Unit Repair.