`97 GP trans balking when starting up a grade

I always keep the transmission fluid and filter changed every 12,000 miles. Lately the car has started balking or stumbling badly when assending a hill, with the car in overdrive. Its not enging related or water in the gas. Its defintely the trans. Is their a solenoid that governs the slight downshift when assending a hill? Just when it down shifts from overdrive, thats when it occurs. Otherwise the car runs quite, shifts well.

Any help or suggestions would be appreciated.

thank you

sounds like pressure control selonoid, expensive fix for such a small part. Just my guess though I had the same problem after I purchased mine used, got it fixed under three month warrenty. good luck

When the car stumbles are the rpms dropping off as well?

Have you tried leaving the trans in 3 for the climb?

I haven`t thought to look at the rpms, but today I got it out on the interstate for the first time since the problem, and I noticed its not necessarily doing it when it down shifts from the overdrive position. Just when you start up a steep grade. If the trans is put in the drive postion and not the overdrive, their is no problem.

If its the pressure control selonoid, where is it located, and do you get a visual from under the car?

I would guess the pressure control solenoid too. I might be having a similar issue.

What it does is send extra fluid into the torque converter into an area that makes the lockup clutch start locking up. There are actually several degrees of lockup, and it could be fumbling around and not locking or releasing all the way. Even worse, the clutch in the torque converter could be shot. I'm hoping mine isn't, but I can just disable lockup with my power tuner under certain speeds where I have this problem.

Oh yeah, I heard that the solenoid is actually a fairly easy fix and you can get to it by dropping the transmission pan. Not sure, though.

thanks for the help everyone. I love the 2 door GT car and have owned it for three years. recently I had decided to take it out of dailey driving duties for work. I had it repainted, new tires, etc. it has 201,000 miles and the oil gets changed every 2000 miles.
Maybe I can give a mechanic some leads to take on the trans or if I get time maybe I can drop the pan and find it myself. does anyone have a description of what to look for?

zuulmusic, how do you disable the lockup?

He uses his tuner. Reprograms the PCM.