Section 347.455 - Modifications to height of vehicle(1) Except as further provided in this section, no person may operate any vehicle on a highway if modifications have been made to the suspension system, axles or chassis of the vehicle which cause any portion of the vehicle to ride more than 4 inches above the height of the vehicle specified by the manufacturer. The height of the vehicle shall be measured from the level surface on which the vehicle stands.(2) If the modification is for the purpose of strengthening or improving handling, modifications may be made to the suspension system, axles or chassis of a 4-wheel drive vehicle or a motor truck which has a gross weight of not more than 8,000 pounds which cause the vehicle to ride 5 or less inches above the height of the vehicle specified by the manufacturer. The height of the vehicle shall be measured from the level surface on which the vehicle stands.(3) A 4-wheel drive vehicle or a motor truck which has a gross weight of not more than 8,000 pounds may be modified to use a tire and wheel size which exceeds the wheel and tire size specified by the manufacturer for the vehicle by up to 4 inches in radius.(4) No person may operate any vehicle on a highway if modifications have been made to the suspension system, axles, chassis or exhaust system of the vehicle which cause any portion of the vehicle, except the tires, to extend below lines drawn from the bottom of each wheel rim to the points of contact between the tires on the opposite side and opposite end of the vehicle and the level surface on which the vehicle stands.1981 c. 216; 1993 a. 165.