Al Dorsa, from Christiansted, US Virgin Islands writes:

The mother of this invention is my hatred of shoveling aggregate out of my pickup truck. I built a shallow wooden box that keeps the stone in one place when I drive, and dumps it exactly where I want it when I get to the site.

The dump-bed box fits between the truck’s wheel wells, where it rests on two or three lengths of 3/4-in. pipe. When the dump-bed is empty, I block it up with a couple of 2x4s to keep it from rolling around while I’m driving. Before loading I pull out the blocks and make sure that the pipes are oriented as shown in the drawing. This dump-bed holds about a half-yard, and the loader operators I’ve worked with so far have been able to fill it without spilling a granule.

To unload, I drop the tailgate all the way down, back the truck up to the dump point and hit the brakes. The dump-bed rolls back, coming to rest with one end on the ground and the other on the back of the truck. I just pull out the end piece, and the rest of the aggregate can be pushed out of the dumper.

Putting this truck tip to work

We took some extra steps and added a few features to Al’s sliding bed before we tested it for ourselves. First, we put a couple of eye bolts and a rope on the forward end of the box. The rope gets tied to the hooks inside the bed with just enough slack to let the box slide out and dump, but not enough that it would fall out of the truck. We also tacked some pipe insulation to the front and back of the sliding box to lock it in tight when the tailgate is closed.

When it came time to dump the gravel, we decided to remove the trucks tailgate to keep the sliding box from damaging it.