I added Lucas tranny additive, cuz my tranny slipped really bad from 1st to 2nd, It helped quite a bit, but still, my car has 171k on it, and the Aamco people talked like it was the original tranny, it did help quite a bit cuz it doesn't slam as often and stuff, but it hasn't made it great shifting, I would reccomend it to help it, but its not gonna eliminate all ur tranny problems, so if you plan on keeping the car, I'd reccomend trying to find out what the problem is with the tranny, rather than use an additive, cuz once you get it flushed and such, the problem will be there right where you left it.