Transmission Rebuild

gsxeclipsed · 05-22-2008, 11:57 AM

Hey i got a free trans with a car i picked up. the guy that gave it to me said it had been rebuilt under 3000 miles ago but was broken. so after collecting dust in my garage i decided to open it up and see how much damage was done. i was pleased to see only one bearing had failed. Now my question is...is it ok to replace this one bearing? or do i need to do more?. ill attach pics of the bearing. the snycros all look good to me but im no expert. i also plan on adding the filter and RIPGRIP front diff insert.

eclipsh · 05-22-2008, 12:52 PM

I've seen a few sets of OEM bearings for a full tranny online. You might check out getting a set and replacing all of them. If one failed the others may too. Bearings are cheap, trannys aren't.

gsxeclipsed · 05-22-2008, 01:46 PM

i did see a set from teamrip.com. the bearings seem to be ok but your right its always better to be safe then sorry. now what is best way to get the bearings off? i think there is a press at work i can use but i need to make sure.

twicks69 · 05-22-2008, 02:52 PM

Quote:

Originally Posted by gsxeclipsed

Hey i got a free trans with a car i picked up. the guy that gave it to me said it had been rebuilt under 3000 miles ago but was broken. so after collecting dust in my garage i decided to open it up and see how much damage was done. i was pleased to see only one bearing had failed. Now my question is...is it ok to replace this one bearing? or do i need to do more?. ill attach pics of the bearing. the snycros all look good to me but im no expert. i also plan on adding the filter and RIPGRIP front diff insert.

That transmission looks like a 90 gearset -- it has the 3/4 synchros that use partial engagement teeth (not the entire way around)

Input Shaft Inner Tapered Roller Bearing MD732314
Input Shaft Outer Tapered Roller Bearing MD726235

Intermediate Shaft Tapered Roller Bearing (1989-1990) MD724117
Intermediate Shaft Tapered Roller Bearing (1991-1999) MD736638

Use Jack's "Gear Set Identification" to see what year it falls into:
Gear set identification

No matter what year the transmission is, it is always worth it to replace the input and intermediate shaft tapered roller bearings, along with properly re-shimming the transmission upon re-assembly.

In this circumstance, it is likely that the tapered roller bearing was either re-used from the last rebuild, or it was improperly shimmed.

Either way, you will want to fully disassemble each shaft to thoroughly inspect the parts so that you don't end up having to rebuild it again if something else is wrong.

Good luck,

gsxeclipsed · 05-22-2008, 05:24 PM

Thanks for the great info!

JackM · 05-30-2008, 10:28 AM

Actually that is a 92ish gear set. Very nice tranny to have as you can just drop in any EVO gear you want with very little to no modifications. I have never seen that input bearing fail, ever. That is very rare. I would take a closer look at the case as there might be something weird going on in there to kill that bearing.

Jack

gsxeclipsed · 05-30-2008, 05:05 PM

I am pretty sure it was not shimed correctly. i hope that was the main cause and no bigger issue with the case. and jack i wanted to compliment you on a great website with some even better info.

JackM · 05-30-2008, 07:26 PM

Oh, thanks!

gsxeclipsed · 06-03-2008, 03:06 PM

i have looked at the case and i cant seem to find anything strange like a crack or if its warped. i did find out that the trans was rebuilt buy a local guy and have talked to him and he has been no help. i guess ill just order new bearings and put it back together. is there any reason i shouldnt do this?

twicks69 · 06-03-2008, 04:36 PM

Jack, thanks for the year clarification on the transmission gearset. I must have been not thinking that day. I should have looked closer at the spare gearsets I had in my garage to have caught that one.

talon187 · 06-03-2008, 04:45 PM

hey jack are the evo gears stronger or better?

JackM · 06-05-2008, 11:43 AM

The gears themselves are not really stronger. The change in gear ratio helps a little but what makes the assembly stronger is the thicker hub and slider it uses. The 93-99 trannies had a weak hub and slider assembly that would break. Replacing it with the EVOIII set cures that problem. The trans in the pics is a 92, so they already have the strong hub and slider.

The EVOIII gears are better IMO due to the double synchros they use. They shift very nice.

Jack