Interesting Transmission "Replacement" Idea

[TalonJohn94]

Please tell me if this is possible

A couple years ago I bought a 1990 ShepTrans race transmission. Well, it is strong but has a lot of "shift block" like when it takes a full second from 1st to 2nd and 2nd to 3rd. Its understandable because it was an old, used transmission.

Currently, someone has a '90 transmission for sale that he says shifts like butter but has a cracked bell housing.

Since I don't have much of a garage, and only basic handtools, I was thinking about buying the cracked transmission and replacing the insides of my transmission on car.

The reason I though of this is I've done a couple center differential replacements and it seems like you could take it apart almost all the way while the transmission was still bolted up.

Any thoughts?

 

[->PrOjEcTGS<-]

Replacing the gear stacks is going to be next to impossible with the trans still in the car. It's hard enough getting them out of the case while it's out of the car. If you really want this thing to work I would take the time to pull it out and go completely through it. And I don't see why you wouldn't be able to do it with just simple hand tools. Since, you won't be disassembling the gear stacks you won't need a press. Just rememember to check the preload on the bearings and shim it accordingly.

 

[TalonJohn94]

Oh ok. For some reason I thought you could just bolt the bell housing to the rest. Like maybe the output shaft(s) just fit through, you bolt it together and install. I think I worked on a 90's Jeep Cherokee that was like that.

But your saying its more of "one unit" - pressed together and all that?

 

[->PrOjEcTGS<-]

Yea on these cars you can't just unbolt the bell housing and replace. It's the bottom section of a 4 part. So in order to change it out you have to disassemble the whole trans. Here's a link to the V-FAQ: 2g Transmission Rebuild

 

[beating4g63s]

Yea on these cars you can't just unbolt the bell housing and replace. It's the bottom section of a 4 part. So in order to change it out you have to disassemble the whole trans. Here's a link to the V-FAQ: 2g Transmission Rebuild

you sir are my hero, I've been looking for information on tearing apart one of our trannys just to learn, and have done a little searching but never even seen this I must be slacking thanks for making it so easy.

 

[TalonJohn94]

I assume 2g and 1g are only slightly different.

I guess I'll have to see if Shep will do this rebuild, because it no longer lists "basic rebuild" on his website.

 

[->PrOjEcTGS<-]

Very slight differences.

 

[twicks69]

GoldDiamond, if you want, I can take a look at your transmission(s), but I am expecting that there are REASONS why it doesn't shift smoothly; such as improper preloads or damage. Usually, just swapping parts from one trans in to the other without reshimming just keeps you with the same problem. Also, the trans that the guy is selling may have more damage than he leads on to, and would need a full inspection at the minimum. What was the reason for the bellhousing damage? I would expect damage to the input shaft also; which effectively means you need a rebuild anyways. You are better off getting a rebuild over swapping out used parts for used parts -- especially since you would need new tapered roller bearings and bearing races installed -- you are not able to just pull the gear clusters and swap them into the other transmission -- there is some work required to do it properly.

I would gladly help you out, especially since you are in the Milwaukee area.

Pull the transmission in your car, and PM me when you are ready to do some transmission rebuild/swap work.

I also have a few spare 1990 parts sitting around, and am very fair on rebuild pricing.

 

[TalonJohn94]

Sounds good, it probably wouldn't be until almost Winter though.