Transmission ?

[chrissbee77]

I have a 2001 grand prix gt 3.8 n/sc. It has 168,458 miles on it. When i put the car in drive it goes just fine. but it seems to be hesitating when i'm on the highway. i was thinking maybee a clogged cat but it checked out fine. I replaced the plugs wires coil pack, fuel filter, air filter and it still does it (it also needed a full tune-up), it seems to be making a whining noise almost like a wheel bearing but it sounds more like a p/s pump. The tranny fluid is a little brown but has never been changed and i was told my a lot of people not to change the fluid with this many miles on it / also no check engine light any ideas.

[Highbeamz]

Well as a general consensus I've read as well, if the fluid has never been changed, don't bother. I treat the automatic transmission like black magic myself...you can learn how it operates, but there's still a touch of voodoo. What type of hesitation are you experiencing?

By the way, going 162,000+ miles on an original tranny is not THAT bad...although bad luck you happen to be the owner of the car if it's going.

[grandprixgtx00]

Originally Posted by Highbeamz

Well as a general consensus I've read as well, if the fluid has never been changed, don't bother.

not so true. its just recommended that you dont do a FULL tranny flush if it wasnt done every 20K...meaning flushing all the fluid out, and putting new fluid in. on your mileage you would be safe doing a pan drop and putting apx. 6 quarts of new fluid in along with the new filter.

GM recommends you do a full flush every 50K, however i do it once a year on all my cars.

as far as your problem goes...i guess you should ilaborate on the problem you are experiencing a little more...

[Highbeamz]

Originally Posted by grandprixgtx00

not so true. its just recommended that you dont do a FULL tranny flush if it wasnt done every 20K...meaning flushing all the fluid out, and putting new fluid in. on your mileage you would be safe doing a pan drop and putting apx. 6 quarts of new fluid in along with the new filter.

GM recommends you do a full flush every 50K, however i do it once a year on all my cars.

as far as your problem goes...i guess you should ilaborate on the problem you are experiencing a little more...

Well I would think a full pan drop would be the best solution as well, but as far as I read up the fluid gains contaminants and whatnot as the fluid ages and these contaminants supposedly aid in not allowing the torque converter to slip. They say when you change the fluid you lose this and the fresh fluid (and now lacking contaminants) can cause slippage of the torque converter because the system became accustomed to the dirty fluid, so to speak. I'm not a fledged auto mechanic and this seems to be a touchy topic, so take it with a grain of salt. Luckily for myself I had the fluid changed before that dreaded 80K Mile mark...