i think the vss sensor just craped out on me. well thats what i think. while driving on the highway the other day the trany started shifting down all by its self in amd out of overdrive. then all of a sudden it down shifted again felt like it shiftrd into first. it made a big bang ! it broke my rear motor mount. i stoped and started going again and it shifted hard threw the gears .then the check engine light came on .