When you stomp on it from a dead stop, feels like either the motor mount or u-joint is bad. Has a vibration and shake that only lasts until the vehicle is in motion. Once in motion, the shake is gone and works and shifts fine. Had the vibration checked out and trans fluid changed by machine at the local national chain tire shop and now the dipstick will not go all the way down. You can push it down but will spring back up 1/2inch when let go. They want to replace the dip stick. They feel the vibration but can't figure out what's the problem. Any advice?