I have a 98 Ford Windstar. The tranny was slipping only after prolong stop and go traffic. It would slip real bad for a while and eventually work as long as the traffic started speeding up. I had a complete rebuilt put in with all new parts. after a few weeks my first time in prolong stop and go it happened again. I plan on taking it back to the shop that put the rebuilt in but I don't have confidence that they would know whats wrong. I'v decided to try to get on-line help. Can you please help me. Thank you for your time.