8.5 Grand National Rear End for sale

[Gearheadwilly]

I've never owned or ran either prior to this purchase and this diff still sits on my floor awaiting attention, but the GN is an 8.5" ring vs the smaller 7.5" or 7 5/8" MCSS, the GN axles are 28 spline vs 26, the driveshaft will need to be 7/8" - 1" shorter, Eaton units are rebuildable and Auburn is not. Like I said, I'm brand new to these things myself so I'm not a great source. There are some excellent sources on this very forum though.

This thread has some decent info.

transmission & rear end upgrade

**A good chunk pf the 80s SSs had 7.625 rear ends with 3.73s and 28 spline axles. Posi was optional. Normal Montes might have had the 7.5 with 3.08 and down.

gbodyforum.com

These forums do as well.

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I had no idea man, i honestly just figured you'd say, the width and the locker were different or something. That's a whole different animal altogether though. Eaton is top notch imo. I've owed one (clutch type, 4.11's) for many years with zero issue. Probably should have looked into it before I asked and saved you some time. I do greatly appreciate the time you took to educate me. I've worked on what my bones register as about a 2many cars at this point in my career but as luck would have it, I've never laid hands on a GN in a shop where I could take a peak at all the goodies in detail or in the air. Thanks man.