trailers??

There is a trailer like that but it's a cover wagon(flatbed witha sidekit). It has hoppers in the center of the floor with trap doors that you open when your gonna haul grain and close them when your gonna haul other stuff. I don't know if it would be what you need to haul pallets. I don't remember seeing aname on the trailer but Wilson comes to mind so check them out.

 

my dad built one around 1992 in utah, for hauling sugar beets.

flat bottom with a narrow 18" conveyor belt in the center.

after the bottom had drug everything out, the floor and sides clam-shelled closed.

this mad the remainder of the load fall to the conveyor.

\_/ looked like this when closed \_/

cool set up, hauled 30% more because of no wasted hopper space.

and no bridging of the load...

 

The type of trailer you are asking about is called a convertible hopper. They are hard to find. Cornhusker makes the only kind I know about,(used to pull one) It was a old green products company trailer a real beast. They are 48ft 102wide and 13ft6in high. The one I used was an open top roll tarp. (seen a few hard tops with hatches before) They have heavy aluminum floors that fold down from the side walls that cover the hoppers; they also have dividers that fold out of the side to divide up the compartments. We hauled sunflower seeds in bulk one way and loaded pallets back sometimes.
pics

 

My old boss has one of those, uses it to haul his finished product on pallets out and haul raw materials in the hopper back. pain in the butt to use a forklift in tho...