Rear Diff compatability

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turboboxer92
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Rear Diff compatability

Post by turboboxer92 »

What is better to rebuild a bad rear diff or replace? Also what years will work and what is the gear ratio?


I had recently replaced my rear cv axles and they were extremely worn. There is still a lot of noise coming from the rear and I feel that its the differential. That could be why the axles went bad in the first place who knows... I don't know what will work as a replacement and are certain years the same? I know they are really inexpensive for used ones I was wondering which ones will fit please help.
rallyak
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Re: Rear Diff compatability

Post by rallyak »

The ones that are a straight swap are 90-94s, you need to check ratio. 90-91 5spd and 4eats are 4.11, 92-94 4eats is 3.90.

My self I'm replacing mine right now with a 01 legacy gt vlsd rear end w/95-99 outback axels, I've done this on my other car and its a nice up grade, and I believe it run smoother.
Charles

90' White/Gray Outback DD workhorse (670,xxx) miles
92' Onyx Metallic (430,xxx) Wife's DD
68' Barracuda formula S 340 4spd coupe (ongoing project)
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cj91legss
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Re: Rear Diff compatability

Post by cj91legss »

Although rallyak gave you some great information, You haven't given us any information about your car. Yes this is an 89-94 Legacy forum, we have many users from later models. We will need more information from you before we can chime in with solid answers.
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
turboboxer92
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Re: Rear Diff compatability

Post by turboboxer92 »

ohh sorry about that its a 92 ss 4eat. I don't think that there would a be a need to upgrade unless it will fit without modification. I was wondering if anyone rebuilds rear ends on these or just replaces. The rear cv's are brand new so It would be nice not to hanve to yet find another pair. Side thought the abs wouldn't have anything to do with this binding issue in the back would it otherwise Im stumped.
cj91legss
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Re: Rear Diff compatability

Post by cj91legss »

Its probably less of a hassle to find a replacement.
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
Legacy777
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Re: Rear Diff compatability

Post by Legacy777 »

All the turbo models 91-94 had 3.90 final drive rear ends. Only the 91 had a VLSD. You should be able to easily find a 3.90 rear end.

I will say though, that these rear ends don't typically go out, so your noise may be a wheel bearing (more common). You may want to see if you can confirm the noise is coming from the rear diff before replacing it.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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