Transmission swap

[ddyke2000]

Hey guys. I have a 2000 gpse 3100 and the transmission went out. I bought another one the other day that came out of a 97 grand prix. All the plugs match and everything looks the same. I just want to make sure that its going to work. Am I going to have any issues or am I safe to go ahead with the install?

 

[Sabrewings]

What trim 97 GP? If it's a 97, it's either a 4t65E HD or a 4t60E. Neither of which is a drop in replacement for yours. If the plugs match, i bet you have a 4t65E HD which has a different gear ratio than your old transmission.

 

[ddyke2000]

so if the gear ratio is different its just going to shift at a different rpm ony right? is that a major deal?

 

[Sabrewings]

A different gear ratio will cause the PCM to throw a Incorrect Gear Ratio code, which will cause it to go to max pressure and bang into every gear.

 

[ddyke2000]

so what would i need to do to stop that from happening

 

[Sabrewings]

so what would i need to do to stop that from happening

Either get the right transmission or get your PCM editted for the proper gear ratio.

 

[ddyke2000]

What actually is the pcm and if it is the old transmission can I just swap the two?

 

[Sabrewings]

The PCM is the computer that controls your engine and transmission.

 

[ddyke2000]

so do I need a pc for a 97 grandprix or can I just reprogram it and if I can how would I program it.

 

[superol]

trans

alright i need some help now
i have an 97 olds 88 that i recently supercharged..and the trans gears are horrible highway gears
i need to know if i can use a 1999 pontiac gtp trans for mine
both 3.8 engines...

 

[Sabrewings]

Re: trans

alright i need some help now
i have an 97 olds 88 that i recently supercharged..and the trans gears are horrible highway gears
i need to know if i can use a 1999 pontiac gtp trans for mine
both 3.8 engines...

Most likely, but you'll need a new passenger side axle, need to swap the fly wheel on your engine or the torque converter in the transmission, and you'll need PCM reprogramming.

Does your Olds use a 4T65E or 4T60E. If it's the 4T60E (like in 1997 Grand Prix GTs) you can forget about the swap.

 

[superol]

yeah it takes the 4t65e trans
it would be nice to have a better trans
instead of one that acts like a powerglide and stays in second across the line lol...
well we will see what happens...
thanks for the help
if you have any other thoughts just let me know

 

[ddyke2000]

so i have got the trans from the 97 in hooked up and ready to go. do i need to have the pcm reproggramed before i start the car or will i be able to drive it to the shop to have them program it?

 

[GPSims39]

i dont beleive any shop can re-program the computer, you need to either get it tuned by a performance shop who specializes in PCM Re-programing, you can get a do it yourself tuner for a few hundred bucks, get a 97 PCM, or a whole new PCM designed to your specs

 

[Sabrewings]

get a 97 PCM,

Won't work since there was no PCM for the 3.1L that had a 2.93 gear ratio.

 

[GPSims39]

ahhhh got ya

 

[ddyke2000]

what wont work. i can still get a pcm from the 97 correct?

 

[Sabrewings]

what wont work. i can still get a pcm from the 97 correct?

See my answer to your question in the PCM section. In short, no stock PCM will work.