Got my LSD in the mail the other day. Thanks Snowman. Looked over the "Frequently Asked Questions about how to upgrade, lift, shoe your Soob for wheeling." write up by Zap.

 

I got a spare diff from work, and I'm going to bring it home tonite and start ripping it apart.

 

The LSD will be going in the car in my sig

My questions so far:

 

1. Will I be using my 3.9 stub axles and NOT the ones on the LSD unit that I have? or the other way around.. stub axles stay with the LSD unit? (Basically I dont want to have to run turbo 25 spline axles)

2. Looking at the LSD unit, I dont see where the E-10 torx bolts are to take off the stub axles. lil help here?

3. Because I got just the LSD unit (and not the diff carrier) I'm not going to be able to compare the two cases. Where am I going to grind on my 3.9 case?

 

All comments appreciated

I got a spare 3.9 diff if you want it.

Since I've done this process many times, maybe I can help. I hope this helps.

 

 

Got my LSD in the mail the other day. Thanks Snowman. Looked over the "Frequently Asked Questions about how to upgrade, lift, shoe your Soob for wheeling." write up by Zap.

 

I got a spare diff from work, and I'm going to bring it home tonite and start ripping it apart.

 

The LSD will be going in the car in my sig

My questions so far:

 

1. Will I be using my 3.9 stub axles and NOT the ones on the LSD unit that I have? or the other way around.. stub axles stay with the LSD unit? (Basically I dont want to have to run turbo 25 spline axles) There is no difference in the rear stub axles, you can use either set.

2. Looking at the LSD unit, I dont see where the E-10 torx bolts are to take off the stub axles. lil help here? Look down the center of the stub axle, they should be hollow, the torx bolt is in there holding the stub axle to the unit.

3. Because I got just the LSD unit (and not the diff carrier) I'm not going to be able to compare the two cases. Where am I going to grind on my 3.9 case? It will be very obvious when you go to put the LSD unit in, but if you look inside the case, you will see some bumps, these are where there are threaded holes for bolts, there should be two on each side, figure out which side will have the contact and then grind them down, it is ok if you expose the hole.

 

All comments appreciated

Here's the write up that Mick put together in the repair/mod section.

 

Pics even.

 

http://www.ultimatesubaru.org/forum/article.php?a=36

 

I should add a link in the FAQ. . .

all rear diffs are 23 splines. the torx bit is inside the axle stub. if the 3.9 case is an ea82 there will be no grinding or drilling. see my attatchment on the article in the usrm

all rear diffs are 23 splines. the torx bit is inside the axle stub. if the 3.9 case is an ea82 there will be no grinding or drilling. see my attatchment on the article in the usrm

????? Most of the diffs that I have converted were EA82s, they all required grinding.

Are the EA81 diffs and the EA82 diffs the same?

 

or at least interchangeable? They look the same?

As long as the rear ratio (3.700 or 3.900) is matched, they are all the same.

Are the EA81 diffs and the EA82 diffs the same?

 

or at least interchangeable? They look the same?

I recently had a hell of a time getting those E10 bolts out on a diff I just did. The heads snapped off, but left the tapered part of the bolt holding in the stub. I talked to a few people and they did not have the same trouble, although some had the bolts snap further down.

 

I had to drill out the bolt down past the tapered section. Good news, the bolts (and the stubs) are soft and drill easily. Bad news, if this happens to you, there is almost no easy way to use a handheld drill and not damage the stub axles mating taper. If I was going to try and save the stubs without any damage, I would have had to chuck up the whole diff in a mill or drill press and drill out the center of the bolt, making sure everything was perfectly centered and perpendicular.

 

The bolt shafts are .389", so a 23/64" is the optimal drill bit to ensure little or no damage. You may want to face the end of the bolt first to ensure your drill bits don't walk on you. You can use a 1/2" end mill for this operation. HSS bits work fine. Once faced, I would use a center drill and then step up size gradually. It's a lot of work, but it might be useful to know this if you don't have another source for stub axle shafts and this happens to you. BTW, this diff was from a 1982 Wagon, lived its whole life in the Salt Belt, so this could be the reason why.

????? Most of the diffs that I have converted were EA82s, they all required grinding.

 

from what i read q-mans article is swapping a lsd into an ea81 and ea81 3.9 gear. my buddy robert swapped a lsd into an ea82 diff case and ea82 ring gear and it all fit and bolted up the same, no grinding or slotting. just passing along the info.

Right on. Thanks for all the info. Gonna have a good weekend project. Just got some new rubber on the car along with the H-alloy rims (blew out two tires this weekend in our 500 miles of wide open rallying).

 

I'm still undecided on the grinding part. I'm hoping I dont, but if I do:

 

Dr. RX - what did you use to grind it? die grinder, or dremel tool? or a grinding bit on a cordless drill?

Dr. RX - what did you use to grind it? die grinder, or dremel tool? or a grinding bit on a cordless drill?

I use a pneumatic die grinder.

Hi, though I've owned EA82 wagons for 20 years, I've never looked inside the diff and I'm utterly ignorant concerning interchangability of parts. So forgive my basic questions:

 

Where do the LSDs come from? Another L-series based vehicle or from later Imprezzas, Legacy or Forrester? Here in the UK one only really ever sees the later cars in the scrap yards because pretty much all the older ones have been scrapped/crushed by now. Can I take and LSD from a later car to fit my '91 EA82 L-series?

 

Also, are the whole diff units (assuming correct ratio) transferable or do they require custom axles/drive shafts and/or propshafts?

 

Hope you can help guys

the clutch type lsd came in turbo models of the ea82 series. the majority were 3.7 geared but i think some xt may have come w 3.9. the cool part is swapping the rig gear out for a 3.9 and keeping your gear ratio

the clutch type lsd came in turbo models of the ea82 series. the majority were 3.7 geared but i think some xt may have come w 3.9. the cool part is swapping the rig gear out for a 3.9 and keeping your gear ratio

 

Clutch-pack LSD came standard ONLY on the RX with FT4WD D/R trans.

It was a roughly $1,000 option for any EA82 with a 3.7:1 geared trans.

99% of clutch type LSD are 3.7:1 , due to the fact that they come out of turbo cars.

A very few FT4WD XT-6's did get the 3.9:1 LSD, but i've yet to see one with my own eyes.

Edited March 4, 201313 yr by Greenley

Many thanks for the info - are any of the lsd units from later cars interchangeable at all?