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The Beast I Drive

Got my LSD fix today

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Tonight I got the LSD from my old RX converted to 3.9 and ready to install in the Beast :banana:

 

However, I have a few after-the-fact questions:

 

1. I overtorqued the bolts that hold the ring gear to the LSD carrier unit. Factory spec is like 58lb ft i was told, but that was after I torqued them to 90lb ft :eek:... Is this going to be a problem?

 

2. I am not a rearend/tranny specialist, and have no clue how to check backlash. When I swapped the LSD into the 3.9 housing, I used the shims that were installed on the housing when I took it apart and I put it back on exactly like I found it. Should I be worried about grenading my pinion gear? Everything feels good, no slop, nice and smooth motion...

 

3. I used RTV silicone to make the rear cover gasket... Because Im lazy and impatient and did not want to wait another week for a gasket from the dealer... No problems there right?

 

4. I used Genuine Subaru LSD oil in it (all the writing was in Jappanese so I couldnt read it :-\), I just filled the diff with it untill it was level with the fill plug. I wasnt supposed to mix it like 50/50 was I?...

 

I got really lazy about this whole piece of the project, I did not clean and paint the housing or polish the cover or put on a custom 3.9 LSD sticker... Its ugly, dirty, and no one would tell by looking that its LSD, But I now have an LSD that will see lots and lots of mud and trails I hope... Cant wait to try it out! Ill test it out this week and then put it to the real test at Evan's Creek :grin:

 

-Bill

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Sounds like exactly what I did. I torqued the crap out of mine!! It's holding up great with man thousands of miles. The only difference I did, was I used regular NAPA gear oil and then used a limited slip additive that I also bought from NAPA.

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that all sounds good to me bill, though i'm clueless about overtorquing those bolts.

 

never done one, but the few i've read about, folks just put them together like they found them so to speak like you did.

 

i have to do the same thing before winter, how long did it take you? an hour or a few?

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All in all it took me prolly 3-4 hours of looking at it, kinda-scraping some dirt, looking at it, taking some parts off, looking at it, spilling 6 quarts of used diff oil all over my power tools, looking at it, swapping the ring gears, squeezing the LSD chunk into the housing, putting it all back together, and torquing it down. My advice is do not put the bolts in the ring gear untill after you get the LSD into the housing, its too tight of a fit, I got it in, but I had to hammer it in with a rubber mallet because one of the bolt heads made it just a few thousandths too tight of a fit... Also use the bolts from the LSD, they are longer becasue the flange is thicker on the LSD... It could be done faster, but It was the first one I did, so I took some time... Oh and I used Red Loc-tite on all the ring gear bolts after I cleaned the threads of the old thread locker...

 

Now its time to weld up the 3.9 chunk and put it in one of my Brats :banana:

 

-Bill

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All in all it took me prolly 3-4 hours of looking at it, kinda-scraping some dirt, looking at it, taking some parts off, looking at it, spilling 6 quarts of used diff oil all over my power tools, looking at it
great, should be about the same for me, sounds EXACTLY how my work usually goes!!!:lol:

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when i did my swap i put the posi carrier into a 90-94 legacy housing. it slipped right into the housing after it assembled it. i used my electric 1/2inch snap-on impact and just put the ring gear bolts on as tight as i can. havn't have a problem at all.

 

then just put in some valvoline 80W90 and some LSD additive.

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Should be fine with the stock shims on the backlash, take a paint pen and draw a line on one pinion tooth face. while the paint is still wet, spin the drive shaft a time or two and look where the paint makes contact. If the paint mark is not centered on the ring tooth, then remove or add shims accordingly.

 

here is a good write up on it

 

http://www.differentials.com/install.html

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