Abstract: An air flow deflector for a snow plow mounted on a motor vehicle having a radiator. The air flow deflector includes a deflector fin for deflecting air flow against the radiator of the motor vehicle. The deflector fin includes a main body having an upper surface, a lower surface and opposite side surfaces. A mounting arrangement is provided for mounting the deflector fin in adjustable angular relation to a top surface of the snow plow and in spaced relation to the top surface of the snow plow so as to define an air flow passage therebetween. An arrangement is also provided for releasably fixing the orientation of the deflector fin with respect to the mounting arrangement.