Abstract: A hydraulic circuit and a wheeled self-propelled moveable frame provides a one-way feed of water under pressure selectively bearing a liquid soap or a liquid rinse chemical via a wind up hose mounted on a spool via a drive motor to axle to belt to clutch to shaft on the moveable frame through a multi-way directional valve to a water powered drive motor for driving the moveable frame forward and reverse relative to an open end of a vehicle body and said spool. A water cylinder changes the angle of inclination of a floor nozzle tube rotatable about its axis horizontally at the front of the moveable frame and bears a series of longitudinally spaced nozzles, when the machine travel reverses towards the open end of the vehicle body. The multi-way directional valve changes the water flow direction upon impact of a sensor operatively coupled thereto and projecting forwardly of the front of the wheeled self-propelled moveable frame.

Abstract: A self-propelled vehicle for cleansing the internal surfaces of a partially enclosed chamber, such as a trailer body, is provided with a battery powered electric motor. The electric motor provides power for a water pump, a drive motor, and hydraulically powered accessories such as cleaning brushes. The vehicle is further provided with storage tanks for housing water, detergents, and disinfectants, which are used during the washing and rinsing cycles. By this manner, a vehicle is provided which is completely self-contained, thus eliminating the need for external power sources and umbilical cords to carry power, water, and chemicals to the vehicle assembly.

Abstract: A more or less conventional back and forth shiftable spray and rotary brush assembly is provided for movement back and forth along the external surfaces of a trailer body to be washed and includes opposite side portions from which inwardly projectable and outwardly retractable wheel washing brushes are supported. This component of the invention is utilized to wash the exterior of a trailer body. The invention further includes an elongated extendable boom structure having a base and free ends. A carriage is provided from which the boom is supported in horizontal position with the base end of the boom supported from the carriage and the free end of the boom extendable relative to the carriage.