For washing the exterior of large vehicles such as trailers, busses, or truck tractors a portable washing device including a rotating brush assembly which can be raised and lowered. Water or other liquid can be supplied to the brush assembly for washing the vehicle. The entire device is mounted on a transmitting chassis capable of sharp turns especially in one direction so that it can move around the vehicle to be washed. The brush is also movable to a horizontally disposed carrying position, or can be tilted to maintain contact with the vehicle even when either it or the washer is on uneven ground.
