rschap1

Thought I'd hit up the GM experts here. Wife's 2000 Pontiac Grand Prix GT has had the tranny start slipping. 1500-2000 rpm surges. Did same when it had about 20,000 miles, now it has nearly 120,000. When under warranty at 20k, the dealer replaced the tranny. Been fine since...well until yesterday. Wondering if there is anything "famous" to look at before I visit the tranny shop.

BanditTA

iTrader: (3)

Is this while the TC is locked? I ruined my first tranny in my buick gsx when the TC went, supercharger boost gave me enough power that it would pull almost any hill with the TC locked. Downfall was it killed the TC because of the load, mine would surge like that, I kept driving it and it sent clutch material through it and ruiined everything in it's path. I'd change the filter first and then if you have scan tool watch the TC slip RPM's.

rschap1

I am imagining that the TC at those speeds and RPMs is not yet locked. I don't have a scan tool for the car, so I may end up depending on the dealer or tranny shop for that diagnosis. I do know that there is 50-60k miles on that filter. I was suspicious of that as soon as she told me about it doing this. Sounds like it better get drove as little as possible until I get to peek at it. THANKS very much for the tips!

HMERacing

I have a 97 GTP that does that from time to time. Think its time for a new Engine/Trans for me. It has a few miles on it and it is 100% original. 232,xxx Miles.

rschap1

Well this turned out to be a bit of a false alarm. Simply checking the fluid level fixed her up. I over reacted when I got the call from my wife while I was at work and jumped to conclusions. VERY GLAD that was all it turned out to be. I'll have to get underneath tomorrow and see if there's any leaks. THANKS for the help!!

Wesmanw02

iTrader: (4)

My GTP will do the same thing, it will easily go up most hills at anywhere from 50-60MPH lugging the engine in the 1400-1600RPM range with boost.

The benefit of the 4T65E though is that it uses pulse width torque converter lockup, meaning it locks up gradually instead of just dumping into lockup. Because of this feature, a paper lined TC clutch would burn up almost instantly, so these transmissions use a Kevlar clutch to lock the TC. Seems to have proven more durable than the older style carbon/paper clutches.

rschap1

I wanted to say Thanks again here! I actually had another thread going regarding the leaky valve cover gaskets on this same Grand Prix. Everyone told me of the problems/recall of them. While this isn't a recalled GTP, it was leaking pretty bad. I didn't want to waste time replacing them, thinking that wasn't the source of the leak, but it seemed a very common problem from what I heard here. Hit NAPA, bit the bullet and spent an hour or so replacing them. ALL BETTER! Thanks to everyone here that helped, much appreciate it, sorry I can't find that actual post.