Tonight i was driving down the highway at 55-60 mph..set the cruise, i was went up a hill i noticed my car feel like it slipped a lil, as if i was in 1st?? go a little farther and my stall completely becomes unlocked??? if feels like im in neutral in 3rd and 4th, but i still have 1st and 2nd????i have a yankss 4000 stall in a stock trans??? Does anyone know whats wrong???