A device for use in dispensing tire chemical onto a cylindrical car tire brush, comprising, an elongated shield having a concave inside surface having a curvature generally matching the outside curvature of the cylindrical brush, a port entering into the inside surface of the shield for receiving a chemical, and at least one distribution groove formed into the inside surface, which distribution groove communicates with the port and is inclined downwardly at an angle so as to distribute the chemical longitudinally along the said inside surface.