482460 Transfer Case Saver, Pump Upgrade, 2001, 2002, 2003, 2004, 2005, 2006, 2007 GM 6.6L Duramax LB7 LLY LBZ 261XHD 263 XHD
The GM transfer cases 246, 261HD, 263HD, 261XHD, 263XHD have an aluminum pump cover that rides against the magnesium hosing. Over time this will wear a small hole in the transfer case. The location of this leak is on the top of the case and will not typically leave a puddle when the vehicle is not in motion. The end result is the case will run dry before the owner is aware of the loss of fluid causing more damage to the internal components of the case.
The case saver will protect the case from wear and distribute the load of the pump more evenly.
GM did install a clip in the later years to help prevent this, however, they have a high failure rate and can be removed when running the case saver.