While cruising at about 40 around a curve on the freeway my transmission somehow found neutral! Every gear simply left all at once. No pop, no jerk. Nothing. Engine just started freely revving. Had it towed to the local shop. They tell me I need a new transmission. I pay for one that came with a 3 year warranty. They pull the old one and put the new one in. Same exact problem still there! What am I missing?