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LSD swap question


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37 replies to this topic

#1 subieman

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Posted 16 February 2005 - 08:33 PM

Does anyone have pictures of a LSD 3.7 conversion to a 3.9? I read the tech article but pictures would speak a thousand words.
Thanks

#2 subieman

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Posted 16 February 2005 - 08:35 PM

Okay this is a stupid question. But I dunno! With a LSD swap into a 84 wagon would I be able to run in 4wd on dry surfaces without the rear end binding up? Something like awd?

#3 ballitch

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Posted 16 February 2005 - 08:41 PM

i believe the LSD only activates when one wheel slips more than normal, going around a corner shouldnt affect the "feeling" of the car, at least i wouldnt think so.



~Josh~

#4 84Scoobaroo

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Posted 16 February 2005 - 08:41 PM

Okay this is a stupid question. But I dunno! With a LSD swap into a 84 wagon would I be able to run in 4wd on dry surfaces without the rear end binding up? Something like awd?


No. The front and rear outputs are still locked, no give in the tranny so it will still bind up.

edit: re-read post, and the rear end wont bind up like a welded diff would, but it would still bind in the front/rear transfer of power. W/ out a front axle it would be a two tire fryer :brow:.

#5 Qman

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Posted 16 February 2005 - 10:40 PM

A LSD rear diff does not change the characteristics of the drivetrain. You have to change the trans for the AWD feel.

#6 Qman

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Posted 16 February 2005 - 10:41 PM

Sorry, I never took any pics.

#7 Wasteland

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Posted 16 February 2005 - 11:17 PM

I just finished my LSD convertion last week and thought the same thing until I got everything apart, and it really is self explanatory. just keep all the 3.9 stuff separate from the 3.7 stuff and you'll be fine.

#8 Sweet82

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Posted 17 February 2005 - 11:12 AM

Isn't there some grinding involved?

I thought the 3.9's wouldn't fit exactly without some metal removed?

#9 subieman

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Posted 17 February 2005 - 06:57 PM

Ok I am going to attempt my first LSD conversion. I'm going from 3.7 to 3.9. Ok I read the the tech article but I don't know the terminology good enough. On the picture below can someone show me what needs to be swapped out. Where is the Ring gear? And which case will I end up using? The original 3.9 housing or the 3.7 LSD housing? Oh and what holes might be to small or to large? Just a little confused.

Posted Image

#10 ezapar

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Posted 17 February 2005 - 07:13 PM

Circled in Red are your 3.9 Open parts.

Circled in Blue are the 3.7 LSD parts.


These are what you keep.
(along with the stub axles from the LSD unit, not shown)

Posted Image

#11 subieman

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Posted 17 February 2005 - 07:16 PM

Thank you!!!

#12 Jibs

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Posted 18 February 2005 - 12:04 AM

Let me know when you're gonna do it I want to come over and see/help. I also have one of my own to do.:brow: Hey and I was thinkin, if you want to use my rear diff for the example, and then give me the you pull out of the wagon when youre fone, that would be all right.

#13 subie94

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Posted 18 February 2005 - 06:21 AM

how much would it cost me to convert to LSD?
also is having a LSD be close to having lockers? (can't you tell i'm new to this):-p

#14 MorganM

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Posted 18 February 2005 - 10:04 AM

how much would it cost me to convert to LSD?
also is having a LSD be close to having lockers? (can't you tell i'm new to this):-p


Close but no cigar. If you lift a wheel you are still screwed with an LSD; the one in the air is gonna spin. However it's still a nice upgrade; definatly the next level in traction control if you have open rear diff.

#15 subieman

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Posted 18 February 2005 - 10:36 AM

Cost is anywhere from $45-$70 at your local pick n pull yard. The price just depends on who's behind the counter that day. Jibs pulled two from two different yards and one charged him 45 and the other 70.

I'm gonna attempt the ratio swap soon and I'll take some pic's and let you guys know if it needs grinding. Which I'm pretty sure it does.

#16 TheSubaruJunkie

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Posted 18 February 2005 - 11:13 AM

I got my LSD from the same yard Jibs went to. I paid $38.50 on 1/2 price day.

Any diff shop should be able to convert the ratio's... just take them the LSD and a good 3.9 diff... and your credit card.

This is really good info tho... answered alot of questions I had.

-Brian

#17 VaporTrail

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Posted 18 February 2005 - 12:15 PM

I added the image with stuff circled to the write-up in the USRM...

#18 subieman

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Posted 19 February 2005 - 03:14 PM

OK I'm stuck. I got the diff apart and now I can't figure out how I can get the gears out of the case. I took the bolts out of the ring gear but nothing is coming apart. Help!

Posted Image Posted Image

#19 TheSubaruJunkie

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Posted 19 February 2005 - 03:24 PM

I believe there's a special tool involved.


-Brian

#20 subie94

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Posted 19 February 2005 - 03:31 PM

I believe there's a special tool involved.


-Brian


you gotta love it when there's a special tool involved :banghead:

#21 subieman

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Posted 19 February 2005 - 04:22 PM

I believe there's a special tool involved.


-Brian

Haha thanks, thats very helpful! :banghead:

#22 VaporTrail

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Posted 19 February 2005 - 06:06 PM

you need to take the stub axles out. that's what requires the E-10 Torx socket. you may need to reassemble eveything first, so as to not damage the bearings on the carrier.....

#23 Jibs

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Posted 22 February 2005 - 12:06 AM

So where in the heck do you get this e10torx socket? I bought one from Napa, but it doesn't fit inside the stub axle. It seems like the only way it would work is if the socket is on 1/4" drive, and nobody in town sells them. I went by Sears, Harbor Freight, Kragen, The dealership, and Napa today, and nobody had them. Where would I get this mystery socket? Thanks.

#24 VaporTrail

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Posted 22 February 2005 - 12:50 AM

So where in the heck do you get this e10torx socket? I bought one from Napa, but it doesn't fit inside the stub axle. It seems like the only way it would work is if the socket is on 1/4" drive, and nobody in town sells them. I went by Sears, Harbor Freight, Kragen, The dealership, and Napa today, and nobody had them. Where would I get this mystery socket? Thanks.


http://buy1.snapon.c...ore&dir=catalog

and Qman posted on another thread about using this with one of the impact drivers that you hit with a hammer to break them loose.

the bolt heads like to twist off, so be careful....

#25 ezapar

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Posted 22 February 2005 - 12:57 AM

A board member told me today he caught an LSD on ebay going for over 300 bucks. It had a reference at the bottom to come to this board to find out how to convert it to 3.9. Wonder what board member it is sniping and using us to help him.




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