Peter F

It must have been from a 1990 GT if it had PSD.
I did the same with a -89GT box in my -81S and no need for any modification.

link to thread with pictures of the swap.
5sp gearbox change

/Peter

Vilhuer

It had full PSD installed and it was really '89 GT and not early '90 MY first registered late '89 calendar year?

Please do check year code from gearbox number when you have a chance.

Giovanni

GaryJ, if the LSD unit in your current transaxle is good I am interested in buying it. PM me.

John Veninger

Giovanni,

You may know this, but the 78-82 LSD unit is a different size compared to the 83-89.

Giovanni

Thank you John, I did not have my reading glasses on :-). I thought Gary already had an 89 GT transaxle.

Rob Edwards

Vilhuer-

Below is a shot of my tranny from my '90, VIN # 278, with a date of Jan 10, 1990 on the doorjamb VIN sticker. Is the '3L' the date code? In American muscle cars, a '3L' would be December 3, but somehow I doubt Detroit and Stuttgart use the same coding schemes.

GaryJ

Thanks guys:

You guys are correct I am planning on having to change the TT but I am not sure if I am going to have to change the bell housing as well, anyone know?


What I am looking at should be the 89GT box it has LSD not PSD and it has been presented as such and I was told when I am off looking for the 5th gear to be sure to get the one for the 89GT so I am pretty sure it is one. Since I have such an old car I don’t think any of the PSD boxes will work. From my time thinking about this project I thought the 89GT box would be the best match for my car.

Apparently it is the main 33:22 drive gear that is bad and the box was in the process of a rebuild but the project was put on the shelf, about the only main part still needed is the 5th gear main drive.

The current LSD is good but is the original 79, actually the box is not too bad if you are just putting around but if you want to drive with a purpose second is no friend at all and third can get very notchy.

I’ve owned my car for over 20 years and am looking to revitalize the car and have something I will enjoy driving for another 20 years which is why I am thinking to go with this newer box. I also plan on some pretty good engine upgrades and I think the 89GT box will hold up to them much better.

Thanks,

Gary

Peter F

I'm very happy with mine in my -81S, it was very easy to swap.
Not sure about the bell housing, maybe Erkka knows?

/Peter

John Veninger

You shouldn't have to change anything up front. Don't think there was any change in the torque tube mounting to the bell, just the length. Jim B. could confirm.

Jim bailey - 928 International

The early upper bell housing is dimensionally the same with various small changes like the size of the ball stud hole, added timing sensor for test purposes. 5spd and auto are the same however only for two disc clutches the 87> auto and 5 speed are different.

Vilhuer

Changes were done in different years and there is sort of continuation in modifications where one part is changed and it works with both new and old version ot other part. This means all different upper bellhousings and torque tubes should work with each other.

Rob Edwards

Erkka-

Thanks for the decoding!

-Rob

BC

So basically, the TT length was dictated by the trans case length. The 78-~80 trans cases were 10mm longer? SO the TT was that much shorter. And the later transmissions were all the same length then (5spd), at least the case length, and the TT was 10mm longer for those years?

DO I have this right? Are there any other dimensional changes on the cases of the 5spds? Width?

GaryJ

Thanks for the information.

So a new TT and I should be in business with the new box. It will be nice to not have to buy ANOTHER piece for the project.

Thanks,

Gary

Jim bailey - 928 International

trans, torque tube, and rear suspension cross member and transmission mounts I believe plus late shift rods lever...