Skip to content
View in the app

A better way to browse. Learn more.

Ultimate Subaru Message Board

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

WRX LSD in EA82 D/R 3.9

Featured Replies

I've done a fair bit of reading and I know an early legacy turbo 3.9 LSD will fit

into my 1987GL wagon d/r. I have easier access to a 3.9 LSD from a WRX.

Does anyone know if this will fit or not, easy install ?

 

Thanks:)

bolts right up but you will have to find the ever hard to find stub axels from a 1991 turbo legacy, i went to the dealer to find some, $225.00 ea and only one in the country. look for a set used. but will fit.

Also Are you talking front diff or rear diff..?

 

Interesting...???

  • Author

Sorry guys it's the rear LSD I am talking. I can get one from a local WRX swap shop. I know the guys and they said they have one that needs a reseal and it's out of an 02 WRX which I believe are 3.9 gearing.

Finding Legacy turbo stub axles may not be too difficult where I am. It's about a 2 hour drive to get this WRX LSD so I don't want to get it unless it might work. I think they wanted $50 for it.

Rick...

 

WRX does not use a 3.9 ratio in the rear. it's actually a 3.54 i believe, WRX tranny is not 1:1 center diff ratio... The front diff is 3.9, but the rear is a 3.54 as the rear is slightly geared down i guess.

 

you ever find those lugnuts btw?

the WRX center diff has a 1.1:1 ratio, thats why the rear diff is 3.545 and the front is 3.90. however, you should be able to put your ring and pinion on the WRX rear diff and it all should be fine, but dont hold me to that. even if its only fifty bucks down the drain, you didnt lose much.

 

 

 

~Josh~

the WRX center diff has a 1.1:1 ratio, thats why the rear diff is 3.545 and the front is 3.90. however, you should be able to put your ring and pinion on the WRX rear diff and it all should be fine, but dont hold me to that. even if its only fifty bucks down the drain, you didnt lose much.

 

 

 

~Josh~

 

Correct. WRX center diff is 1:1...but the output shaft GEARING is for some reason is 1.1:1...and rear diff is 3.545.

 

The 'old school' 3.900 ring and pinion is the SAME as the 'new school' R&P sets...use it. It's been done more times that I have eat at Subway (WJM eats at subay 1~2 times a day, and has done so for the last 4+ years).

  • Author

Thanks for the help. I will buy the WRX diff. and swap the parts as outlined in the FAQ section.

 

(Do it Sidewayz, still looking for pug alloy lugs for my 15's, and some 14inch steel pug wheels if I come across some, Peugot parts in Canada are very scarce)

just got a set of turbo legecy stub shafts. turns out the clutch stub is just smaller in diamater than the WRX. so i will have to find a new way to mate the WRX diff.

Please sign in to comment

You will be able to leave a comment after signing in

Sign In Now

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.