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

1. Inspect all of the bearings and journals. Refer to Transfer Case Front Half Cleaning and Inspection , Transfer Case Rear Half Cleaning and Inspection , Rear Output Shaft Cleaning and Inspection , Front Output Shaft and Input Shaft Cleaning and Inspection and Drive Chain, Drive Sprocket, and Driven Sprocket Cleaning and Inspection.
2. Replace any faulty bearings, and any components with faulty bearing journals. Refer to Front Output Shaft Drive Sprocket Bearing Replacement , Front Output Shaft Rear Bearing and Rear Output Shaft Bearing Replacement , Input Shaft Thrust Bearing Replacement and Front Output Shaft Bearing and Front Input Bearing Replacement.