Montana Title 61. Motor Vehicles § 61-9-407. Fenders, splash aprons, or flaps required on certain vehicles--dimension and location

(a) If the vehicle is equipped with fenders, the fenders must extend in full width from a point above and forward of the center of the tire or tires over and to the rear of the tires.

(b) If the vehicle is equipped with splash aprons or flaps, the splash aprons or flaps must extend downward in full width from a point not lower than halfway between the center of the tire or tires and the top of the tire or tires and to the rear of the tires.

(c) If the vehicle is in excess of 8,000 pounds gross vehicle weight or rating, the fenders, splash aprons, or flaps must extend downward to a point that is not more than 10 inches above the surface of the highway when the vehicle is empty.

(d) If the vehicle is 8,000 pounds or less gross vehicle weight or rating, the fenders, splash aprons, or flaps must extend downward to a point that is not more than 20 inches above the surface of the highway when the vehicle is empty.

(a) when measured on the cross-sections of the tread of the wheel or on the combined cross-sections of the treads of multiple wheels, the fender, splash apron, or flap extends at least to each side of the width of the tire or of the combined width of the multiple tires; and

(b) the fender, splash apron, or flap is capable at all times of arresting and deflecting dirt, mud, water, or other substance that may be picked up and carried by the wheel or wheels.