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Fried Rear Diff?

Featured Replies

With a 5 sp manual, Subaru recommends the TEMP spare be put on the front.

 

Thinking you have that backwards. Spare on back, fuse in FWD override.

Thinking you have that backwards. Spare on back, fuse in FWD override.

 

manuals dont have a fuse, only automatics do :rolleyes:

 

nipper

  • Author

Sure 'nuf. Looked for override fuse when the heat was on Lil' Su (manual) and couldn't find it. I was just thinking of my previous Subie, 1990 Legacy Wagon AT.

 

BTW: Rear diff's "hum" gets pretty loud around 60 mph. Picked up a new (used) rear diff at the yard yesterday. Paid $175.

Cool, but 175? Seem a little high was it a refurbished diff? Or used low mileage, or diff u dont know but was said to be new but is used? Also just wondering, hey niper if there is a wining noise in the rear, is that a bad thing? Its not super loud but but there in the back u can hear it only. Anyone there know if it is bad, i also got the diff fluid changed.

manuals dont have a fuse, only automatics do :rolleyes:

 

nipper

 

That's weak. Makes sense though.:o

  • Author
Cool, but 175? Seem a little high was it a refurbished diff? Or used low mileage, or diff u dont know but was said to be new but is used? Also just wondering, hey niper if there is a wining noise in the rear, is that a bad thing? Its not super loud but but there in the back u can hear it only. Anyone there know if it is bad, i also got the diff fluid changed.

USED, from salvage yard. New to me! Called all the yards around (within hours drive). Prices from 250-175. Took the 175.

There is a LSD on ebay if anyone is interested...

 

 

nipper

I might be, let me check it out. I see a few but u have a link where i can outbid you:grin:

  • Author

So, I'm ready to tackle the removal and installation of the rear diff. Uncharted territory here. What tools and steps will this involve? Can I just unbolt it and drop it and plan on there being enough play in the halfshafts? or do I have to take them off (or just one side?). How about the driveshaft? I shouldn't have to remove that, right? And tools, anything that I should be aware of? Thanks ahead of time!

  • Author

So, the diff I got from the salvage yard says it's a 4.111 ratio. I thought my car (90 Legacy L Manual AWD sedan) had a 3.9. Correct? But, from ye olde photo below you can tell that my diff's label is long since gone.

 

What gives? I told the guy at the yard my year, make, and model. He said he had it and I went and picked it up. Today I started the project and got to thinking, "I'd better double check what that label says." So, am I right that this rear diff I just bought is NOT going to work?

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do you know what year the "new" diff came out of?? thats the only way you'll ever know. or open the both up and count the teeth, but thats not something i'd ever do.

 

there are some web sites for parts that might help with what years are compatible. first subaru parts, or genuine subaru parts, or maybe car-part.com. you can search the year you have and see what others years will match. not a garrantee, but it might help.

 

from what i've read recently, manuals don't match a/t's, and 2.5's don't match 2.2's. but the chances are good that a 90 leg man diff was used on lots of cars.

 

good luck.

 

 

So, the diff I got from the salvage yard says it's a 4.111 ratio. I thought my car (90 Legacy L Manual AWD sedan) had a 3.9. Correct? But, from ye olde photo below you can tell that my diff's label is long since gone.

 

What gives? I told the guy at the yard my year, make, and model. He said he had it and I went and picked it up. Today I started the project and got to thinking, "I'd better double check what that label says." So, am I right that this rear diff I just bought is NOT going to work?

As far as I know, those numbers dont mean jack. You can see that you used to have the sticker on the rear diff. Do a search, there is a post floating around that I started about rear end ratios on Legacys. They use a 3.9 and a 4.11. I think 89-91 were 4.11 and 92-94 are 3.9. I can't remember off the top of my head, I'm used to lookin at the serial # on the tranny and I use that to tell myself what rear diff to use

I'm used to lookin at the serial # on the tranny and I use that to tell myself what rear diff to use

how does that work? are you talking about the tz102 model number or the other number on the trans.

 

from one of the parts supplier web sites, first subaru i think, i found that all 96-99 a/t 2.5L leg / outback have the same rear diff. but i have no idea what that is. this seems to be one of the most mysterious areas of subaru info. my manual doen't even mention the final drive. hopefully the FSM does.

  • Author

Jury says 4.11!

 

Well, suggests 4.111 here: http://www.ultimatesubaru.org/forum/showthread.php?t=57742

 

This is confoundingly convoluted: http://www.ultimatesubaru.org/forum/showthread.php?t=52723

 

And this says non-turbo 90-94 Leg's were 4.111: http://www.ultimatesubaru.org/forum/showthread.php?t=2616

 

Also, found these for those who want a ton of info: http://surrealmirage.com/subaru/trans_spec.html

http://surrealmirage.com/subaru/motor_trans_combo_spec.html

 

And if all else fails, look in the owner's manual!

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