I was driving the truck, went to pass a car slowing to turn, as I accelerated, I heard a loud bang, no forward or reverse gears. When the engine is running, if I put it in gear, it engages the pump, you can see the RPM change. I lost no fluid, the trans did not leave a giant fluid spill on the road. I'm guessing tail shaft on trans or input shaft on transfer case. I drain the t-case and I can see the chain is still intact. I haven't had time to pull the t-case yet. Has anyone had this issue? If so, what was the end result? I do't think I need a new trans. The tranny does have a shift kit, I do have a programmer. I was running the 80 ecno tune from DP at the time. I am not blaming the program, just giving info.