One of our accounts brought in a 2007 Ford F-450 with a 6.0 diesel engine and a 5R110W TorqShift transmission, complaining of a delayed engagement in reverse. The driver also complained that if he decided to accelerate hard just before coming to a stop, the transmission would neutralize and then engage harshly.
But inside the transfer case closest to the transmission is the transfer direct-clutch drum that the sealing rings just love to dig into. The severity of the wear determines the degree of the complaint; i.e., delayed engagements, slipping or no movement. Technicians often misdiagnose this problem by blaming the transmission for the problem when all along it has been in the transfer case.