Hello, My little brother has a '99 Grand Prix SE with the 3.1L in it, and I believe the trans is a 4T60E, but I posted in this section because it is a 97+.
Anyway, he was complaining about it slipping or not shifting properly into 3rd, I had my mom's b/f drive uit because he is more mechanically inclined or would be able to give me more info on what it was doing since I wasn't able to check it out and my brother is about as knowledgeable as a flea for diagnosing car problems and explaining them. Yada, yada he confirmed it having a slight slip or what not and then we decided to change the filter and a few other things that needed to be done on it.
So the filter is changed, as are the other things (sway bar was broke on one end and the RR wheel bearing shot), we get it down and replace the trans fluid that had been drained with the filter replace (put new fluid in, obviously). So my mom's b/f goes and drives it and its basically doing the same thing, check fluid again and its fine. So at this point not sure, I guess leave it be.
So my mom and brother came to pick it up tonight and they warmed it up for like 15-20 mins before leaving and it wont shift at all when its warmed up. You get going down the road and it just wont shift, once you get to like around 35mph it starts to do shake like it wants to shift but it wont.
Any ideas?
