A bed leveling system for a dump truck to prevent an imbalance of the truck bed during unloading of material. The system controls the side to side tilt of the truck bed and returns that bed to a generally level orientation when the bed tilt exceeds a predetermined angle. The truck bed is pivotally affixed to the truck chassis through a hinge pin. Thus, the tilting of the dump bed is carried out by a hydraulic system that changes the tilt of the hinge pin. The leveling system includes a cylindrical tube that supports the hinge pin and which is rotatable with respect to the chassis. A roll cylinder rotates the cylindrical tube to change the tilt angle of the hinge pin. A tilt sensor senses the out of level orientation of the truck bed and activates the leveling system to bring the bed back to a generally level orientation.