16065 Service Update. Certain vehicles may have been assembled with a suspect gear set in the rear differential module (RDM). Specifically, the back face of the pinion gear in the RDM may have been cracked during the manufacturing process. If a crack propagates and a gear tooth fractures, it could wedge into the ring and pinion gear mesh interface and cause the rear wheels to lock up with the potential for loss of control of the vehicle. Dealers are to replace the rear differential module.