1998 RS 5MT center diff into a 2000 RS 5MT ??

[Richard_Donovan]

Both are 5-speed
can these two center diffs be interchanged?

if not can i at least put the front ring and pinion gears in my 91 front drive 5-speed Legacy??(option 2 )

I have a 2000 RS and the center diff and bearings are bad.

I bought a 1998 RS trans with a broken first gear from a friend.
Will it work?

thank you,
Richard Donovan

[carsucharda]

it sounds like you dont have access to a press. in order to replace the front diff assemblies you should replace the ring and the pinion gears as a set. if you dont you may end up with some preload issue or noises. also if you can remove the transmission and split the case yourself you could always take your front diff in to a local shop out of the case and have them press on two new bearings for a lot less trouble. theoretically they are the same transmission i would double check the final drive and remember there are many things that would require a press if you went the swapping parts from one to another route and you were oging to do it the right way. if you are just going to replace the part of the diff with the ring on it thenwho knows how long it will last. id seriously consider taking the ring and spiders into a shop and having them press new bearings onto it and throw it back into the good trans. they should both be 4.11 though

[BAC5.2]

Carsucharda - I don't think you are exactly aware of what you are saying.

First, he's talking about swapping the center diff. No press necessary, and you can even do it with the trans in the car. That said, no the 98 diff won't fit in the 00 case. The counter and pinion shaft splines changed in 99 when Subaru changed the synchro engagement hub design.

Second, To swap the ring and pinion gears REQUIRES swapping both the ring and pinion gears. It's a differen't gear ratio. If he didn't have to swap ring and pinion gears, then it wouldn't be an issue.

Third, There are no bearings to press on in order to swap ring and pinion gears. Strip down the case and pull the counter shaft out of the trans. Unbolt the rear crown nut (which you can't do without special tools), slide the pinion shaft out, and repeat on the new transmission. Torque it right and make sure it's shimmed properly, which is difficult if you don't have a bunch of shims on hand. Unbolt the ring gear and swap that over to the new diff, and call it a day.

What you need is another newer style transmission to get the diff from, or another older style transmission to swap the rear section from the 98 off of.

Either way, make sure the rear diff matches whichever front diff you need.

Theoretically the gear box is identical. Practically, it's not.