12 Bolt

[69keith]

I just bought a 12 bolt out of 69 wagon. I got a gut locally that has a jig that he says he can put the 10 bolt tubes in it.. Anyone done this? He has done 3 or 4 in the last year for builder that builds COPO clone cars. The builder buys these dated rearends and puts them in the 69 cars so they have matching #s rearend.

[ProdigyCustoms]

They have been done this for a while. Camaro vendors have been doing it. it worksd, good for a hot rod, horrible for a restoration.

[69keith]

I think the tubes on a 12-10bolt are the same, but are the axles different?

[Turbo Hen]

12 bolt axles are 30 spline, 10 bolt axles are 28 spline.......thats if dealing with pre-80's stuff as now the 10 bolt 8.5" diffs come with 30 spline in the trucks.

-Carm

[big gear head]

The 10 bolt and 12 bolt use the same axle bearings and seals, so that is not a problem. There are many people doing this, but the tubes must be installed right or they will leak oil. They also must be pressed in straight or there will be excess wear on the differential and axle splines.