§ 74.050 REAR FENDER SPLASH GUARDS.
   (A)    It is unlawful for any person to operate any motor vehicle of the second division, except a truck tractor, to which this section is applicable, upon any highway of this city unless the vehicle is equipped with rear fender splash guards of either the contour type or the flap type which comply with the specifications provided in this section for the type of splash guards used on the vehicle, and which are so attached as to prevent the splashing of mud or water upon the windshield of other motor vehicles.
   (B)   Specifications for contour type splash guards. When contour type rear fender splash guards are used, they shall contour the wheel in such a manner that the relationship of the inside surface of any splash guard to the tread surface of the tire or wheel shall be relatively parallel, both laterally and across the wheel, at least throughout the top 90° of the rear 180° of the wheel surface; provided on vehicles which have a clearance of less than five inches between the top of the tire or wheel and that part of the body of the vehicle directly above the tire or wheel when the vehicle is loaded to maximum legal capacity, the curved portion of the splash guard need only extend from a point directly behind the center of the rear axle and to the rear of the wheel surface upwards to within at least two inches of the bottom line of the body when the vehicle is loaded to maximum legal capacity. There shall be a downward extension of the curved surface which shall end not more than 12 inches from the ground when the vehicle is loaded to maximum legal capacity. This downward extension shall be part of the curved surface or attached directly to the curved surface, but it need not contour the wheel. Contour type splash guards shall be wide enough to cover the full tread width of the tire or tires being protected, and shall be installed not more than six inches from the tread surface of the tire or wheel when the vehicle is loaded to maximum legal capacity. The splash guard shall have a lip or flange on its outside edge to minimize side throw and splash. The lip or flange shall extend toward the center of the wheel, and shall be perpendicular to and extend not less than two inches below the inside or bottom surface line or plane of the guard. Contour type splash guards may be constructed of either a rigid or flexible material, but shall be attached in such a manner that, regardless of movement either by the splash guards or the vehicle, the splash guards will retain their general parallel relationship to the tread surface of the tire or wheel under all ordinary operating conditions.
   (C)     The slow-moving vehicle emblem required by divisions (A) and (B) must meet the specifications and mounting requirements established by the department. The specifications and mounting requirements shall be based on the specifications adopted by the American Society of Agricultural Engineers and published by that body as ASAE S 276.2, dated March, 1968 or as ASAE S 276.5. No advertising or other marking shall appear upon the emblem except that specified by the American Society of Agricultural Engineers to identify the standard to which the material complies.
   (D)    A slow-moving vehicle emblem is intended as a safety identification device, and shall not be displayed on any vehicle nor displayed in any manner other than as described in divisions (A), (B), and (C). A violation of this division (D) is a petty offense punishable by a fine of $25 for the first offense and $75 for a second or subsequent offense within one year of the first offense.
(ILCS Ch. 625, Act 5, § 12-710) Penalty, see § 70.999