Tranny Swap

[pokesmot]

I've been considering a tranny swap for quite some time...

and im in the process of planning an actual swap (starting by getting a used tranny for me to rebuild); but was wondering about the transmission used in the 94 - 98 grand ams with the 3100 engine.

is it the 4T60 or 4T60E ?

If its the 4T60 a swap is going to painfully easy, as the tranmission mount will bolt right up on the drivers side, and the passenger side mount will be the only one in need of custom fabrication. All I would need is the PRND module for the console, and some TCC wiring changes which can be ironed out later.

If im also not mistaken, the bellhousing bolts on the 3.1 and 3.3 will match up perfectly as well.

but yea, I just basically need to know what transmission is used in the 94-98 grand ams with the 3100.

[DomestikDemon]

4T60E= Electronically controlled.
4T60 = Vacuum controlled

Prolly the first one is what you need

[curtisjade1]

Edit: beet me to it lol

[Matt95GT]

The 3100's use the 4T60E ...which would be difficult to make use of since your PCM doesn't know how to control it.

Interface between 4T60E and the 94-95 OBD 1.5 PCM...
http://fazeshift.org/pics/albums/userpics/3100PCM/6E3-A-8.jpg

Best bet... use the 4T60 vacuum operated version (IIRC they can be found in a early 90's Cutlass) and mix and match parts from a 3100 donor car. Not sure how much hacking is involved to make it physically fit on a 3300 though.

[pokesmot]

Originally posted by Matt95GT
The 3100's use the 4T60E ...which would be difficult to make use of since your PCM doesn't know how to control it.

Interface between 4T60E and the 94-95 OBD 1.5 PCM...
http://fazeshift.org/pics/albums/userpics/3100PCM/6E3-A-8.jpg

Best bet... use the 4T60 vacuum operated version (IIRC they can be found in a early 90's Cutlass) and mix and match parts from a 3100 donor car. Not sure how much hacking is involved to make it physically fit on a 3300 though.

does anyone happen to know if the halfshafts that fit into the 4T60E and 4T60 would be the same?

another thing im wondering,

http://www.powertraincontrolsolutions.com/content-4.html

you can get aftermarket PCM's to control the tranny... still researching the possibility that I might be able to solely control the tranny with one of these modules

[Matt95GT]

Not sure on the CV shafts, although I'd say the shafts for a 3100 powered GA would stand the best chance of being the right size.

Neat little box, but at $700+ I wouldn't bother.

[pokesmot]

well I found out what I already pretty much knew... my current tranny is falling apart, there is craploads of play on the passenger side where the halfshaft goes into the differential, so much that it clunks loudly going over bumps.

still shifts ok for now, but im sure its a matter of time before it gushs tranny fluid everywhere or the diff grenades on me.

-----------------------------------------------------------------------------------

im going to rebuild a 4T60 and put it in for sure, not going back to the crappy 3 speed; but i still havent figured out exactly which tranny im going with.


the 4T60E would drop in very easily, because the tranny mount on the drivers side can be reused; would only have to custom fab one mount for the passenegr side which is easy enough.

the one main problem i see, is controlling the tranny... the 4t60e is controlled by the ecm that also controls the 3100 IIRC.

the 4T60 (vacuum) would be easiest... but the problem is that I would most likely have to custom fabricate mounts for both sides which would be a little more difficult.


so if anyone has any ideas on how to control the 4T60E then i would love to drop it in!!

otherwise, im going to have to go for the vacuum controlled 4T60... which might be harder to install.

[DomestikDemon]

Originally posted by pokesmot
well I found out what I already pretty much knew... my current tranny is falling apart, there is craploads of play on the passenger side where the halfshaft goes into the differential, so much that it clunks loudly going over bumps.

still shifts ok for now, but im sure its a matter of time before it gushs tranny fluid everywhere or the diff grenades on me.

haha...yea im about to fix my Astro...the only thing is once its running, Im still going to be in that exact same predicament you are.....from what your saying it sounds to me like your diff is on its last leg/tooth/spline too....I guess the race is on....who will walk home first:???::lol: