[HomeMadeSin]

Now that I have the title in hand for my '67 C-20, the time to start getting my butt in gear is upon me. And I'm looking of guidance from collective, starting with the rear axle...

But first, I do want to stay 3/4 ton and have ZERO desire to convert to 5 lug pattern. I'd rather stay 8 lug.

I have the Eaton HO52 with 4.56 (open) diff. That coupled with the SM420 transmission makes for a relatively high rpm drivetrain, especially with today's highway speeds.

I'm inclined to keep the HO52 and build around it. Why? Good question, but I think I'd rather drive a Prius than do a "belly button mod" (350+auto+14 bolt). And I would never own a Prius - not even if it was free.

And of course, this will lead to the engine discussion and what really gets under my skin. Every single thread (here and elsewhere) seems to follow the tractor beam thought of more cubes the better. Sorry, had to vent a bit.

So first, is today's highway speeds detrimental to a vintage 4.56 diff? Specifically the HO52, which doesn't have the load bolt as I understand it. If prolonged highway speeds is truly an issue, then I will look at the alternatives.

Thanks in advance.

Z