[bdk1976]

I picked up a 8.2 rear this past weekend off of craigslist with a 3.08 posi (4 pinion) and have a couple of questions.

The origin of this thing is unknown and I don't readily see any id stamps (heavy coat of POR15). The thing that jumps out at me is the flat spots on the axle tubes. Is this normal on some years or is it some sort of shadetree mod? All of the 65/66 rears I have are round in this area.

Also, I know the 'proper' answer is to use the matched set of gears, but was just wondering if it were possible to swap only the ring gear with one from a 3.23 rear (both share same # of teeth on pinion gear) and have any chance of success/longevity (assuming I get a decent pattern).

Will likely rebuild it with 3.23, but looks like it was recently gone through and was just kicking the idea around in my head and it got me wondering...

[b-man]

Flat spot on the axle tubes is normal, I've seen it on some '69-'70 GP 8.2 10-bolts.

Even though the pinion tooth count is the same, there is no way a 3.08 and 3.23 set can mate up, very different tooth mesh.

The only chance for longevity is a matched ring and pinion set, and even then you need some luck to set up a used set correctly to make it last.

Your 3.23 gear set can be used with the 3.08 posi carrier. The 2.93, 3.08 and 3.23 gear sets are all compatible with that posi unit.

[bdk1976]

Thanks- makes sense about the gears meshing. I just noticed the same tooth count and started wondering. Will probably end up swapping over the 3.23s.

Thanks for info on the axle tubes as well.