Inspect for the proper transaxle and gear oil levels prior to performing system diagnosis. Refer to Transfer Case Fluid Replacement.

Loose propeller shaft mounting bolts

Tighten the bolts, as required. Refer to Propeller Shaft Replacement.

Loose torque tube bracket or a damaged bracket bushing

Tighten the bracket bolts or replace the bracket, as required.

Incorrect gear oil

Replace the gear oil. Refer to Adhesives, Fluids, Lubricants, and Sealers.