Check the Rear Drive Cup on the Transmission. It is Notorious for comming loose.
Thanks for the help. Had to pull the tranny out to re attach the cup set screw (with loctite) because the brake was in the way. But now I know how to pull it apart and I have 4wd drive as well as brakes again. and the amazing part is that there were no spare screws left on the bench when I was done. Thanks Again !!!!