son in law goes to drain engine oil on this perfectly running 3.5 auto and drains the transfer case by mistake. fills the engine up wth another 5 qrts of oil. car starts and they drive around the block and notice the car jerking and running like crap so they turn around and come home after about 2 miles. he swears to me that he drained the engine oil and nothing else. i fly out to them (military in ft. knox on a tight budget) to figure it out and find 10 gts in the engine and nothing but a half qt or so in the transfer case. drain and fill accordingly and the car will NOT move. engine sounds perfect. pulled off and cleaned the control module going to the case twice as per instructions found here. checked tranny fluid. rolled car back and forth in and out of HI/LO and N with tranny in park. moves in neutral and engaged and locked in lo/hi so it appears transfer case is ok...........i'm stumped and they need their car with the new baby. any thoughts on what to do check next would be GREATLY appreciated.
BTW if I rev it hard it starts to move in reverse only but only a foot or so.
Thanks