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Jaybob · 01-28-2021, 11:29 PM

I know this is an old thread but I am interested in this topic. Have been looking and measuring and I swear the the 73-80 12 bolt is narrower than the 81-87 10 bolt. As far as I can tell the 73-80 12 bolt is 63.5" axle to axle or 63.75" WMS to WMS. The 81-87 seems like it is a little wider at 64.25" axle to axle or 64.5" WMS to WMS. I have measure my 78, but I don't have a square eye square body to compare to. I am building my own 15x11 rally wheels and fitment and backspacing choice is crucial. It looks to me that you would need different offset as they are different by 3/8" per side.

Anyone else have verified 81-87 2wd 10 bolt rear axle widths?

01-28-2021, 11:29 PM	#12
Jaybob Registered User Join Date: Jan 2013 Location: Alberta, Canada Posts: 7	Re: 89 Chevy rear end width I know this is an old thread but I am interested in this topic. Have been looking and measuring and I swear the the 73-80 12 bolt is narrower than the 81-87 10 bolt. As far as I can tell the 73-80 12 bolt is 63.5" axle to axle or 63.75" WMS to WMS. The 81-87 seems like it is a little wider at 64.25" axle to axle or 64.5" WMS to WMS. I have measure my 78, but I don't have a square eye square body to compare to. I am building my own 15x11 rally wheels and fitment and backspacing choice is crucial. It looks to me that you would need different offset as they are different by 3/8" per side. Anyone else have verified 81-87 2wd 10 bolt rear axle widths?