1G 1g transmission compatibility 91-92 to 93-94 swap

[slikvik]

I recently found that my transmission is slipping. After searching for a while I could literally find nothing about the questions I have. The question I have is unique, I have a 1991 Galant GSX 4g63 non-turbo auto AWD. I am going to turbo the car and I already have the turbo 6 bolt engine and supporting mods. My only problem is the transmission.

There is a local dsm'er who has a 1994 AWD Auto turbo tranny for sale.

My questions.

1) Are the earlier auto transmissions (w/ 3plug tcu) interchangeable with the later (2 plug TCU) trans? My car has the 3 plug TCU and the newer tran's came from a car with a 2 plug tcu.

2) Can I still use my stock transfer case, torque converter and rear diff. (remember mine are from a non turbo awd galant). I don't know if the gear ratios are different.

3) If I cant swap the turbo trans, can I use the rebuild kit from a turbo awd dsm to rebuild my galant one. My trans code is w4a32. The turbo trannies are w4a33.

Thanks in advance.

( I am aware that my car is non-turbo, I already have a 3 plug turbo tcu)

 

[brownfinger]

The gear ratios are probably different. Search off of this forum, as your particular question is sort-of out-of the purview of this forum. Someone on here has the info you need, but you could get it elsewhere, quicker. The Tuners answer is likely to be: Use a matching 1G MT AWD trans, T-case, and rear end. You should get a useable result from that.

Edit: OK, search for AWD 1G AT stuff. I just assumed you'd swap to MT. I guess there is plenty of AT stuff out there, too. I just have trouble thinking about why anyone would want AT... My bad.

 

[slikvik]

Edit: OK, search for AWD 1G AT stuff. I just assumed you'd swap to MT. I guess there is plenty of AT stuff out there, too. I just have trouble thinking about why anyone would want AT... My bad.

I already have a 12 second 91 Eclipse 5spd, that's at 30 psi on E85. I have had 6 DSM's in the past that were all 5spd. I just want to try building an auto to try something different.

Believe me I have tried searching and found nothing on here about swapping trannies between earlier to later 1g's.

 

[NOSLO2PT0]

1) Are the earlier auto transmissions (w/ 3plug tcu) interchangeable with the later (2 plug TCU) trans? My car has the 3 plug TCU and the newer tran's came from a car with a 2 plug tcu.

2) Can I still use my stock transfer case, torque converter and rear diff. (remember mine are from a non turbo awd galant). I don't know if the gear ratios are different.

3) If I cant swap the turbo trans, can I use the rebuild kit from a turbo awd dsm to rebuild my galant one. My trans code is w4a32. The turbo trannies are w4a33.

1. The TCU's are not compatible, simply because 1 has 2 plugs while the other has 3 plugs.

2. The vfaq shows the Galant GSX gear ratios, but that's a 5spd. Highly doubt you would be able to find the gear ratios for the auto trans without a TON of digging. Your best bet would be to find someone parting out an AWD Auto drivetrain and buy the whole thing and swap it.

3. Once again, info on that trans is so limited, you might have to call up Mitsu and see if they are compatible.

 

[19Eclipse90]

According to what I have in front of me (which is the "Service-Manual-Transmission-FWD-Mitsubishi-Automatic.pdf" from 3SX Performance - Service Manuals Backups 3000GT / Stealth#-#Mitsubishi 3000GT#/#Dodge Stealth Parts), the W4A32 gear ratios are as follows:

1st - 2.846
2nd - 1.581
3rd - 1.000
4th - 0.685
Reverse - 2.176
Final - 4.422

The gear ratios VFAQ isn't perfect, so it doesn't come as a huge surprise to me that the 1G auto AWD gear ratios are wrong on the page. I don't think I've really ever had a reason to look at them until now, but now that I have, it shows another error. In any case, the manual in the link above matches the FSM I have on hand so I would go with that. Here's what they give for the (correct) 1G auto AWD gear ratios:

1st - 2.551
2nd - 1.488
3rd - 1.000
4th - 0.685
Reverse - 2.176
Final - 4.422

So with respect to the final drive ratio, they two should be compatible (the auto rear ends have the same ratio as well 3.307). To answer your third question, the two use different overhaul kits.