Rear differential for 92 ss

[FrozennorthLGT]

Long story short my 92 has had the trans and diff changed to ones from a 91 NA. The previous owner blew up the diff and couldn't find a 3.9 ratio for cheap so he swapped the whole drive train from his 91 in. The trans is supposedly fine, and I'd like to put it back in because the one in there is probably going to die soon. What cars have a diff that will bolt in? I assume I can use the drive shaft that's in there now. The car is a 4eat since I know that matters. I'd like to keep the axles that are in there and change as little as possible. From my searching it seems any rear diff from an auto Turbo 91-94 ss will work, what about a manual? Would the diff from any newer subi work?

[Legacy777]

I'm not sure I follow exactly what you're trying to do.

Is the 91 non-turbo auto trans that is currently in there dying? If so, what signs are you seeing?

Or are you just wanting to go back to a turbo auto trans?

This thread has info on all the different final drive ratios.
http://bbs.legacycentral.org/viewtopic.php?t=32148

As long as you match the correct final drive ratio between the trans & rear diff, you can pretty much swap whatever you want.

[FrozennorthLGT]

The non turbo trans that is in there isnt the best. First, it doesnt shift 2-3 well at all. It flares up and slips for a second or more before it catches. It supposedly has a shift kit that was installed by a local tranny shop that does "less than stellar" work. It also grinds/whines ALL the time when accelerating or decelerating. ITs hard to describe. IT makes a very loud whine on startup when its sat over night, but not when its warm and it sounds like it comes from the trans not the motor. It sounds like a gear noise, not engine noise. I would rather reinstall the original turbo trans and just want to make sure that all I need is the correct ratio rear diff.

From the sounds of it, all the auto drive shafts are the same, so I can use the one in there now. The Torque converter and flex plate could be from either transmission, I dont know, but what Ive read suggests that as long as you use a matching set, either N/A or Turbo, they will work. I havent done a stall test yet to see if I can tell which one is in there. I dont want to do that yet because I dont have time to do this swap yet and I dont want to break anything...lol.

So it sounds like all I need is a 3.9 Rear diff, and my research seems to say any one from a turbo legacy ss, or from a 91-94 loyale thats 3.9, will work. I just dont want to get into changing axles or anything else. This is just a beater that I picked up for $300, and have about that more into it, so I want to keep it as cheap as possible.

[Legacy777]

Sounds good....Yeah just match the rear diff.

[FrozennorthLGT]

Excellent. That's what I was hoping to be able to do.

[__TT__]

where are you located Frozennorth?

[MikeyMeyagi]

ive got a good used turbo auto trans sitting here...