Abstract: A tiltable cargo box assembly for mounting on a vehicle, supporting a load, and transporting the load into and out/of the vehicle and includes a cargo box adapted for receiving the load therein. An attachment assembly is connected to a rear end of the box for pivotally mounting the box to the vehicle adjacent a rear axle thereof. A ramp assembly for carrying the load is slidably mounted to a floor of the box for reciprocating movement between extended and retracted positions relative to the floor. An actuator is mounted toward a forward end of the box intermediate the attachment assembly and a forward axle of the vehicle for being operatively connected to a power source of the vehicle and cooperates with the attachment assembly for moving the forward end between a lowered position and an elevated position wherein the floor is tilted at an angle relative to the lowered position for permitting the load to be transported into and out of the box.