I have a 1997 Z34. This has truly been the most fun car to drive I have ever owned. When my job changed and my commute went from 40 miles day to 5 miles a day I started driving my pick up to work and the car sat and was very occasionally driven for about a year. I started driving it again. It has plagued me with problems since the rebirth and I am shocked. I picked it up at 53,000 miles and have put 45 on it without even adding oil between changes. It has performed flawlessly. I decided to sell it and the instant I hung the For Sale sign on it it has revolted with the fury of an angry woman. First it was running terrible, a good fuel system cleanup solved 95% of it but it still is a poor performer from startup to warmed up and occasionally sputters yet when its cold. Once it's warm, it's fine. Now the transmission (z34, 3.4 so i am told it is the 4t65 and not the 4t60) is very slow engaging in the mornings in both forward and reverse and 90% of the time it completely disengages when I stop for a light or whatever reason. I can get it to reengage by throttling up slightly until it clunks back into gear and then it is fine until the next time you come to a complete stop. It only takes a few hundred RPM to get it to enagage and it is a VERY LIGHT TOUCH because when it engages it brings back reminders of 1976 and a stall converter. It also seems to be slow shifting but it performs well other than the enagement problem. I will be taking it to aamco next wednesday but i thought i should get educated first if possible. I am hearing a bad front seal and both places i talked to are saying overhaul for 1400 to 1800 dollars. My thoery is since it is only disengaging when I stop could it not be a vacuum problem thats is worsened by the power brakes when I am using this. Would a sudden drop in vacuum to a trans that may be just getting enough to function cause the trans to disenagage. To my knowledge it has never been serviced.

I am hearing the 4t65 that was put behind the 3800 is a different gearset than the one i have also so does that mean if i go to a salvage yard for a trans i have to get a 4t65 from a 97 monte or ltz lumina (3.4) as the 3.1 got the 4t60 trans. if so then thats not going to be an easy trans to locate. will the later ones put behind the 3800 work.

and lastly is this something the viewers at home want to try? I have dropped alot of RWD trans but this one is a complete sub frame drop to get it out? I am assuming i will have to raise the car off the subframe?

in closing,

this sucks

before rebuilding the trans, put some trans-medic in it to see if it's gummed up from sitting.

How many miles are on your car? Have you EVER changed the trans fluid? Should do that after about 40k.

Well, it's a little late I think to be changing the fluid. I have a line on a 4T65E-HD transmission for 2002 Pontiac Grand Prix GTP with 3800 Supercharged engine. This is the Heavy Duty trans, code 'XA' , part number 24215926 on tag. It fits 2002, 2001, 2000, 1999 and 1998 model year W-body cars with the 3800 Supercharged engine.

Does anyone know if this will replace the 4t65e in my 97 Monte z34 with the 3.4? It has a 4t65e in it now. I have heard the gear ratios is probably different. Will this swap work?