Transmission Question

Advice?

I am not real sure what to do at this point, as it would seem this would only get worse.

2004 Grand Prix GTP Under 30k miles, still under warranty.

Has 3.4" pulley, and tuned pcm with proper air/fuel mixture for 3.5" plus aftermarket airfilter.
I can get an oem pulley back on the car; and the dealer I guess would reflash the pcm at some point trying to figure this out. It only started doing this recently.

Getting it to shift out of 2nd into 3rd is not easy. Every other gear or shift works great; no issues.

It will normally not shift until at least 3000 rpm 2nd into 3rd. Sometimes if at 2500 rpm I can let off throttle quickly and it will shift into 3rd. Or if going downhill it will shift out at low rpm no prob.

This is oddly worse on level road; and steady throttle which is slowly gaining speed. It seems maybe the s/c is not really being used at this point; and perhaps less torque? I dunno.

I changed the fluid out last week and this seems to have helped.
The old fluid was black, dark and seemed burned but did not have a burned smell.
The fluid is now pinkish.

The main problem is that if I am doing this at WOT on the interstate; which I no longer attempt; it will hit 6200 rpm in 2nd and not shift into 3rd. Hitting some kind of limiter in the pcm which does not allow it to go over 6200; then stall out the car. (redline is 6250). Unless I back off the throttle a bit; then it will shift at any point over 3500 rpm. no problem.

Not sure if dealer would fix this; should I put car back to stock and see?
I was thinking of getting extended warranty as well.

Any ideas what is wrong, it seems mechanical as the fluid being so dark in color?

'04 GTP with under 30K miles and you are having those problems so soon. It's sad but it happens.

Due to the condition described about the tranny and fluid I'd recommend converting it back to stock and let the dealer resolve the issue. Sounds like the tranny has internal problems like possibly second/third clutch, forward band, sprag gear or even valve body including upshift solenoid problems, etc. I do not normaly recommend a full flush but it sounds like you will need one. The dealer is well equipped to handle this and has the proper GM approved flushing equipment.

You might consider taking an extended warranty and do not wait under for the bumper to bumper to expire otherwise you may have some big $$$$ repair bills.

BTW - Welcome to the forum.

RidnGTP,
keep us posted on what the out come is with your GP. I have a 2004 CompG with some similiar problems with my GP.