GMC Repair: 2002 yukon denali transfer case, yukon denali, gm dealership

Question
A friend bought this vehicle, but, unbeknown to him, it was in hurricane Katrina.[WET!] What he asked me to try to find out is this: Is there anywhere to find a diagram of how the transfer case is put together? He has tried everything, when it gets hot, it knocks. [4x4, automatic transmission,] I do appreciate your tolerance with my ignorance. Thank you  Sincerely, Cyndy [asking for Julio]

Answer
Hi
My best advice would be to check with your local GM dealership and see if they'll print you out the repair procedures fo this case. IF it is the NP (New Process) NVG 149, there is no repair, it is a one speed case.
I hope this helps.
Good luck
Pawl