Assuming LSD needs to be rebuilt.......but......

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Biggin0822

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So when I take off straight or turning right, My gm12 bolt is a peg leg. but when iturn left I can kick the tail out nicely. I've never rebuilt a lsd but it can't be too hard. Can it? What are the pitfalls?
 

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So when I take off straight or turning right, My gm12 bolt is a peg leg. but when iturn left I can kick the tail out nicely. I've never rebuilt a lsd but it can't be too hard. Can it? What are the pitfalls?
Setting it up can be tedious. You will need a dial torque wrench for sure.
 

hatzie

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First off... Are you sure it's a limited slip diff? GM didn't put those in our trucks as a factory option. They installed Eaton Gov Loc locking diffs in trucks with the G80 option.

The G80 is a locker not a LSD. Doing burnouts or hole shots or whatever you want to call em shock loads the diff in short bursts. The Eaton G80 Gov Loc doesn't put up with un-even chattering engagement at full torque very well which is why burnouts quickly feed them to the all-gone machine. :Grenade: Actually, most diffs and transmissions don't like that kind of abuse. You play. You pay.:gr_grin:

Eaton and several others make a clutch pak LSD that has clutches and plates that can be replaced... Those are not G80 Lockers and were not available stock parts on these trucks. Auburn makes a cone-clutch LSD unit that can be re-built with new clutch parts as well.
You need to know what you have so you can order parts.

As long as you aren't pulling the pinion out and you keep track of the position of the side bearings and shims (put them back exactly where they came from) it should be fairly straightforward to replace the clutches and re-assemble it.

Depending on mileage, bearings, axles, Ring & Pinion, and spider gear condition your project may snowball.

Pinion bearing replacement and pinion depth adjustments are tedious and not pleasant or easy without the right expensive tools and some experience. My first axle was an 8-3/4" Mopar rear in my Polara. I had an older friend that helped me out when I admitted I was in over my head.
 
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Biggin0822

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Ya it is lsd because straight line burns were not a problem before. And an open diff would not spin both tires while turning left. Or right or straight for that matter. Pretty sure my 1/2 ton 305 (originally) didn’t come with a 12 bolt posi but I’m sure it came with a 10 bolt open diff. I’ve never had a project that didn’t snowball, lol. Why should this be any “diff”errant??
 

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Ya it is lsd because straight line burns were not a problem before. And an open diff would not spin both tires while turning left. Or right or straight for that matter. Pretty sure my 1/2 ton 305 (originally) didn’t come with a 12 bolt posi but I’m sure it came with a 10 bolt open diff. I’ve never had a project that didn’t snowball, lol. Why should this be any “diff”errant??

If it's an LSD it's not stock GM. You need to find out who made it and what model it is so you can order the right parts.

A locker would burn both tires too...
 
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