Quote Originally Posted by JokerTypeR
My thought is that he blew a ring, or possibly messed up a valve...think about it, it forced the engine to try to turn backwards while it was in motion forward. I know it CAN be the tranny, but usually those tranny's are a little stronger than that...

Do you have a major loss of power, or have you checked for any smoke out the back? Let us know what you find...
engines don't change directions the crankshaft & mainshaft going into the transmission always turns the same direction...then the transmission changes the rotation of the axles or driveshaft.