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Discussion Starter · #1 ·
So we tore apart the truck today to swap the bad G80 with one from a 96 1/2 ton g80. The ring gear fit perfect, the axles slid in and fit, but the kicker was that the neck where the bearings go onto is significantly thinner. I went to autozone and the bearings they looked up and sold me to fit the new g80 but do not fit in the axle housing, they are too small. The original g80 had 77 stamped on it and the 1996 had 17 stamped on it. Does anyone have instructions where I can see how to tear apart the g80 and I will just swap the insides? Or does any one have another g80 lying around from a 99 or newer silverado? Thanks.
 

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GMFS slowest truck :read:
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they use different carrier bearings between obs and nbs trucks. i believe if you do get the correct bearing and race for the carrier, it will work.
 

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Discussion Starter · #3 ·
Does any one know the correct carrier bearing for a NBS?
 

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you dont need NBS carrier bearings. you need bearings to put an 8.5" G-80 into an 8.6" 10 bolt axle. Call up randys ring and pinion and they will have what you need.
 

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Discussion Starter · #5 ·
Thanks, I'll give Randys a call tomorrow.
 

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Discussion Starter · #7 ·
You are misunderstanding the situation, I don't need a master rebuild kit, the 8.6 bearings will not fit on the 8.5 g80 and the 8.5 bearings are too small to fit in the 8.6 axle, I need 8.6 bearings that will fit 8.5 g80.
 

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Bayou Surface Drive, LLC
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Dark eternal Is who told me the information about you getting the the 8.6 master install kit. They are universal because i put an 8.6 Detroit tru trac in my 96 with an 8.5 rear axle. Worse comes to worse go to a bearing shop bring your old bearings and on bearing that i sent you on the carrer. have them match you a bearing that has th right OD for your housing, and the right ID for the carrier.
 

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Discussion Starter · #9 ·
I just got off the phone with Randys, they said it won't work. A custom bearing or race would fix my problem though.
 

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Bayou Surface Drive, LLC
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See how much custom bearings are if not get a damned tru trac they are better man.
 

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Swamper Brotherhood
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My g80 just blew in my tahoe after 164k miles on it. I went with the true trac. Marcus when i looked up info on the true trac it said you could put it on 8.5 or 8.6 ring gear. just make sure the spline count is the same i am guessing. I hope I enjoy mine once the pinion seal and transmission is fixed
 

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Discussion Starter · #12 ·
I was doodling in class and came up with this. Can I have a sleeve between the bearing and the G80 or will catastrophic failure occur. I have buddies that can machine the sleeve so if it is a plausible idea I will have them go make it.
scan0002.jpg
 

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Bayou Surface Drive, LLC
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No you dont want to do that man. it has to be a press fit, if not the bearing will spin on the journal which is not good. It should work man. They gave you the wrong bearing i think. It has to be able to work both ways man because my tru trac was for an 8.6. gotta be universal other than the bearings. i think auto zone fucked up IMO.
 

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Discussion Starter · #14 ·
Hmm, back to the drawing board.
 

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Left Jizz
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A "custom" bearing would be the better fix. A sleeve introduces another part and point of failure. A bearing supply store should be able to set you up something that will work. You would be amazed at what is out there already made that will work in different applications.

From what I understand, measure (with a quality caliper) the O.D. of the G80 shaft, and the I.D. of the housing. Then just call some bearing suppliers and tell them what you need, and they should be able to get you something that will be exactly the size you need, or within a tolerance that will be acceptable.
 
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