It's really surprising how little support the beds are given for the weight they are
supposed to carry. Sitting atop a half dozen little wooden blocks to carry a half or 1 ton
of weight, and I'd bet that every one of these old work horses has carried twice their
rated load many times over in their lifetime.
I just now went out and jumped on the corner of the '97 GMC and the '15 Silverado,
both are 1/2-ton trucks and the only thing that I see moving is the suspension. The
boxed frames are so much more rigid than the open C-channel frames on the AD. That
makes me wonder why it took so long for them to figure out that design feature. The
boxes on the new trucks are still only supported at a half dozen spots, but the brackets
that mount them are pretty substantial and they’re bolted to the side of the frame with
large plates, where our AD box is just held down by those long skinny thru-bolts.
Another improvement that one notices is the unit construction of the new box vs the slab
side AD box. That along with a box frame and the way the box is mounted makes for a
very rigid unit behind the cab. I suppose if you wanted to get a more solid feel from your
AD, you could box the frame and improve the bed mounting. And of course that's why a
popular mod was boxing the frames from the earliest days of hot rodding.
Denny Graham
Twisting, turning and shaking in Sandwich, IL
Last edited by Denny Graham; 06/05/2015 12:52 PM.