Vehicle in-service/out-of-service rotatable tailgate mechanism

An apparatus for rotating a tailgate assembly pivotally mounted on a truck body for movement between in-service, closed and out-of-service positions, the truck body having a bottom floor, a front slope, a canopy extending forward of the front slope, and two side walls for carrying a load and being mounted on a heavy-duty, off-road truck for movement between lowered and raised positions, the tailgate assembly having opposing side beams attached to the respective side walls at their first ends and attached to a tailgate at their second ends, the apparatus comprising:

• a first rotation actuation assembly connected between the tailgate assembly and the heavy-duty, off-road truck for rotating the tailgate assembly between the in-service, closed position and the in-service, open position for dumping the load when the truck body is in the raised position, and
• a second tailgate rotation actuation assembly attached to the truck body for rotating the tailgate assembly between the in-service, open position and the out-of-service position in which the tailgate assembly is positioned at the forward end of the truck body and for locking the tailgate assembly in the out-of-service position wherein the second tailgate actuation assembly comprises in actuating cylinder for positioning a cam into engagement with the tailgate assembly so that the cam may exert a rotating torque on the tailgate assembly.