A counter-balanced top wheel assembly for laundering a vehicle includes a frame. A brush support arm having a first end and a second end is pivotally mounted to the frame adjacent the first end. A counterweight support arm having a first end and a second end is pivotally mounted to the frame adjacent the first end. The second end of the brush support arm is in communication with a brush such that the brush extends over a vehicle bay to launder an exterior of the vehicle. The assembly includes a pulley mechanism with a strap connecting the brush support arm to the counterweight support arm. The brush support arm and the counterweight support arm extend away from the frame in the same direction. The assembly is configured such that the brush applies consistent weight to the exterior of the vehicle throughout its entire arc of travel.