My 2003 3500 Ram w 48re auto trans is behaving badly at slow speeds. While running at +/- 30 mph it will shift up and down between 2nd and 3rd wildly. It also acts like the torque converter is locking. It acts fine when cold, but exhibits this behavior when warm. At higher speeds, and under heavy throttle it acts fine. It is going into the dealer tomorrow. Anybody have experience with this?