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Discussion Starter #1
Does anyone know about these rears on these trucks? Some people say they have clutches some people say no.Mine drives me nuts when i have it in four wheel drive does duck walk with front end can only use 4 wheel drive when going straight SUCKS been this way since new people say i have to live with it. Feels like the gears are welded together like we used to do on the old dirt cars.
 

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Yes, the G80 has clutches.
 

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Discussion Starter #4
Bought truck new have changed oil Amsoil syn put in an additive that a friend gave me he's service man at a GMC dealer. Put that in 20,000 miles ago he told me to put it in 4 wheel drive and do figure 8 turns in parking lot didn't help! Haven't seen him in a while but when i do i'm going to have him drive it and see what he thinks.
 

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Bought truck new have changed oil Amsoil syn put in an additive that a friend gave me he's service man at a GMC dealer. Put that in 20,000 miles ago he told me to put it in 4 wheel drive and do figure 8 turns in parking lot didn't help! Haven't seen him in a while but when i do i'm going to have him drive it and see what he thinks.
These rears dont require the positive additive. Some say it causes problems if you put it in. While there are clutches in these rears. The g80 is basically a mechanical locker.
 

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Discussion Starter #9 (Edited)
GM has an additive for this rear. Thats what i put in said GM additive on the bottle. I thought it was a locker rear too, but it seems like there are many opinions. If gm has an additive it shouldn't hurt it right?
 

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GM has an additive for this rear. Thats what i put in said GM additive on the bottle. I thought it was a locker rear too, but it seems like there are many opinions. If gm has an additive it shouldn't hurt it right?
Some say the additive will actually make these things sticky and make them chatter/hang up.

Yes GM has a limited slip additive. This rear is not really a limited slip, rather a locking differential. It does not call for additive. Just a sythetic ( i think the rating is GL5) gear lube.
 

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I found the video when I was trying to understand how our factory lockers work, it does a great job of explaining it. I've heard that you can remove the governor assembly, add some more clutches and it will work like a traditional posi rear end. I'm personally not a fan of how the g80 works, one of these days I'm gonna tear it apart and see if it can be made into a posi.
 

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I found the video when I was trying to understand how our factory lockers work, it does a great job of explaining it. I've heard that you can remove the governor assembly, add some more clutches and it will work like a traditional posi rear end. I'm personally not a fan of how the g80 works, one of these days I'm gonna tear it apart and see if it can be made into a posi.
Removing the Gov lock parts and cramming some extra Disks in there will essentially leave you with a Dana Trac Loc stye limited slip.

So basically it will most likely be as useful as a set of perky, picture perfect D-cups on a Nun.
 

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Dang, I thought I had a cheap work around figured out. I had a cj5 with a track lock, it was useless. I like your analogy.
 

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Most top brand gear lube already have a LS/FM in them already. GL-5 synthetic 75w-90. The gear lube u used (in this case was Am$oil) u didnt need to add the LS additive shot. By adding extra LS additive it could cause problems with the clutches. Id drain it & just add the GL-5 gear lube.
 
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