Considering replacing tranny

**puma1297** · 01-21-2011

I have a 1998 GTP with 185k on it. Original trans is beginning to fade, but my motor is running strong. Recently replaced the supercharger snout, coils, plugs, wires, etc. Heads are good, no coolant leaks, been extremely well maintained, I think the motor has plenty of life left in her. I want to hold onto this car for another year or two, and I believe that the tranny is the only thing holding me back. I have read many posts regarding transmissions on the forums but have never posted, I usually read and do my work without posting! However, any feedback on the ease of replacing my original 4t65e with a new one (I have found some good deals) would be appreciated!

**cliffdawg** · 01-22-2011

do u plan on modding your car or keeping it stock

**puma1297** · 01-23-2011

well i have made my own cold air intake, relocated the computer, the new snout came with a 3.2 pulley and i upgraded to msd coil packs and 8mm wires. threw some e3 diamond fire plugs in as well. my main focus is just to keep the car running. she runs like a champ, throttle response is great and i have no issues with the engine, just the transmission is starting to question itself. I figured if I keep the car and replace the trans, i would upgrade the pcm to accommodate for the intake and 3.2" pulley, but i dont plan on doing many more mods than that.

**01gpgt01** · 01-23-2011

You cant run a 3.2 pulley with just a intake. You need Extensive mods to run that pulley. Read this and follow it. E3 plugs are also a bad idea. http://www.grandprixforums.net/safel...car-17482.html

**puma1297** · 01-23-2011

sorry it is a 3.4" pulley! came with my magnuson nose drive to replace the stock one. ive read that whole thread as well. dont plan on replacing fuel rails or anything like that.

**01gpgt01** · 01-23-2011

You dont need to replace the fuel rails for a 3.4 pulley. You do need exhaust mods, like ATLEAST a downpipe and Plog

**01gpgt01** · 01-23-2011

you run to hot a spark plug I can guarantee you will pop a piston. Run some autolight 104's get exhaust mods and run the 3.4 with a tune

**puma1297** · 01-23-2011

so would you think that in order to extend the life of the vehicle with the small amount of modifications i have made, i should have an extra tranny on hand, plus downpipe and upgrade the pcm?

**01gpgt01** · 01-23-2011

Id do a plog, downpipe, autolight 104 spark plugs and tune. Your trans will be fine. I made 280whp on a stock GT trans for years till it failed.

**puma1297** · 01-23-2011

I will look into a plog and downpipe. as far as the plugs are concerned, i havent had any issues with running the e3 at all. im not lookin to pull anymore power from my gtp, i just want her to maintain as a reliable daily driver for another couple of years!

**01gpgt01** · 01-23-2011

You're listening but your not hearing me. THE PLUG HEAT RANGES are very important. I do not know what heat range E3's are but Im pretty sure they are going to be to Hot of a plug. to hot of a plug will Kill these motors

**01gpgt01** · 01-23-2011

NGK.com

**puma1297** · 01-23-2011

roger that, i will look to switching my plugs. that rear slant is no fun though haha! also, what downpipe would you recommend? i appreciate your quick response too!

**01gpgt01** · 01-23-2011

ZZP's downpipes are nice. http://www.grandprixforums.net/consi...tml#post492453

No problem. I try to help where I can.

**puma1297** · 01-23-2011

think summit has zzp pipes?

**01gpgt01** · 01-23-2011

No.

**puma1297** · 01-23-2011

thanks man, i will browse zzp website and see what i can dig up. i will look into the plog, downpipe and i reckon i will change my pricey e3s back to something different. i love my gtp and i want her to last me as long as possible.