B body 8.5 10 bolt

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Master Mechanic
Mar 30, 2016
Lockport, Il
So I have this 8.5 10 bolt out of a b body wagon. So from the parts and scraping the car I'm ahead little bit.
Question is do I have it shorten to G body specifications or would it cost to much to for this work. Has any one had thoughts on this or is it way out there in left field


Comic Book Super Hero
Supporting Member
Jan 4, 2009
Wellston, OK
Easier than finding a G body 8.5, but you'll still have to address the upper mount geometry and lower mounts


Royal Smart Person
Feb 16, 2009
Western MN
Kinda. They need to be modified. I am pretty left field, so buckle in for the oddest way to save money on your rear axle you've seen lately :p.

I am planning on doing another 8.5 10 bolt for wagon this summer.

I did a zr2 s10 8.6 rear which works but is too wide. C5 wheels solved that. Long term i want to go back to 15" wheels with 4" BS so I am going to cut the rear I built (below) to stock G width and upgrade axles since I shattered a stock 30 spline axle. I am a special case though (500+ hp stick blown LS2)

My next build is to take the stock 7.5 g body rear and cut the tubes half way between the housing and the LCA bracket and remove the whole 7.5 center section. I have a spare 8.5 center section from a zr2 on hand so I am going to cut the tubes in a similar place and butt weld the 7.5 axles to the 8.5 carrier. Then I will bolt the plate I make (below) and bolt to the 8.5 carrier.

I will end up with
stock 7.5 rear- Free
8.6 out of a zr2 S10, 1500 silverado, or a B body (A b body posi rear is the best since you can keep the stock carrier in place since they have a clutch posi stock)- $150
Sandwich plate UCA mounts- lots of my time but if I ever get around to making them like I said 2 years ago- $175-200
Moser 30 spline GN width 8.5 axles from summit-$250
Yukon clutch 30 spline carrier (optional for B body but i would do it for a gov lock, i grenaded mine) $300

If you "buy" the setup I will end up with it's $900 plus time, which is roughly what a GN rear costs but you have upgraded axles. It's about 600 bucks less than most 9" new I have seen by the time you end up with a carrier worth a damn.



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