Folks,
My neighbor has a stock IRS in his old school rail, and 3rd and 4th are no longer working.

I have another tranny in my yard, but the input is slightly different. On his, there is a collar held in with 3 bolts that the throw out bearing rides on. On mine, there is no collar.

Are these trannies interchangeable? Will the clutch he has now work with the T/O bearing in my tranny? What is the diff on these trannies?

Thanks!
-Kenny

The trans with the collar over the input shaft is a later year trans. The collar is there to guide the TO bearing. Your trans and his clutch are not interchangable. But you can remove this collar from your trans and then use his TO bearing. The three holes that hold the sleave on bottom so you don't have to replce the bolts to prevent oil leaking out. You may need to change the TO bearing fork, I don't remember.

I'm not positive, but the gearing might also be different since later year cars had more HP, so taller gears could be used for a higher top speed.

The reason you need to do this is obvious after you compare the two different TO bearings. The one that rides over the sleave has a larger diameter surface that rides against the pressure plate than the other. If you try to use the non-sleave TO bearing on a pressure plate which would be used on a sleave type trans, the pressure plate will rip the TO bearing out of the fork and even mangle the fork. I know this from experience by not paying attention to this.

So the moral of the story is make sure the TO bearing is a perfect match to the pressure plate.