Abstract: In a vehicle, especially a utility vehicle, aerodynamically acting device for reducing the aerodynamic resistance are provided at the corners between the side panel and roof and at the corners between the side panel and rear end. The flow around the edge between the side wall and roof, especially under side wind conditions, is optimized by means of a bent roof surface (7). At the rear end, the side panel and the roof surface are also bent (7) in a form that tapers the flow around them. For further resistance reduction, blowout openings (8) are provided on the edges of the rear end, by way of which openings either back pressure air from the relative wind or pressurized air from the fan is blown out obliquely to the center axis of the vehicle, so that the static pressure of the rear-end surface is relatively increased and the aerodynamic resistance is reduced thereby.

Abstract: A forwardly-opening scoop is positioned at the upper rear of a snowplow or the like, and a downwardly directed duct portion communicates with it to direct air downwardly along the vertical rear wall of the truck. The device has multiple air outlets, to distribute the air to different areas, to maximize the cleaning effect. Preferably, the device extends down to cover the full height of the rear wall, and includes an air outlet at the bottom edge so that tail/brake lights are also washed by air. A reflective checkerboard preferably is displayed on the device.