Mich. Comp. Laws § 257.710c — MI Code / Chapter 257 / Act Act-300-of-1949 / Section 257.710c
Bumpers; height limitations; lift blocks; prohibited modifications; construction of section; applicability; definitions.
Status: in_force

Sec. 710c.

(1) A person shall not operate a motor vehicle on a public highway or street of this state unless the vehicle is equipped with a bumper or other energy absorption system with an analogous function which bumper or system is securely bolted or permanently attached on both the front and rear of the vehicle. The bumper or energy absorption system shall be maintained in good operational condition, except as provided in subsection (5). Notwithstanding subsection (6), a person shall not drive a vehicle having a raised or lifted body height unless the vehicle is equipped with bumpers that comply with this subsection and subsection (2).

(2) A person shall not operate a motor vehicle of a type defined in subsection (8) that exceeds either of the following limits:

Vehicle Type Frame Height Bumper Height Passenger vehicle 12 inches 22 inches Other motor vehicle: Less than 4,501 pounds GVWR 24 inches 26 inches 4,501 to 7,500 pounds GVWR 24 inches 28 inches 7,501 to 10,000 pounds GVWR 26 inches 30 inches

Vehicle Type

Frame Height

Bumper Height

Passenger vehicle

12 inches

22 inches

Other motor vehicle:

Less than 4,501 pounds GVWR

24 inches

26 inches

4,501 to 7,500 pounds GVWR

24 inches

28 inches

7,501 to 10,000 pounds GVWR

26 inches

30 inches

(3) If the GVWR cannot be determined on a motor vehicle other than a passenger vehicle, the limitations for a motor vehicle having less than 4,501 pounds GVWR shall apply.

(4) Notwithstanding subsection (2), a person shall not operate a motor vehicle having lift blocks between the front axle and springs, or with lift blocks that exceed 4 inches in height between the rear axle and springs in addition to those provided by the original manufacturer. Any body lift block shall be of single piece construction and shall not use more than a 3-inch spacer. Any suspension lift block shall use an alignment pin between the axle and the spring, and shall be of single piece construction. Spring shackle replacements shall not exceed the original equipment manufacture length by more than 2 inches, and coil spring spacers are prohibited. All steering components shall be geometrically arranged to function as original equipment manufacture. Welded pitman arms, drag links, and tie rods are prohibited. All parts used to modify the original suspension or height of a motor vehicle shall be factory manufactured and shall meet or exceed the original manufacturer's specifications.

(5) A person shall not modify a vehicle to be in violation of this section, alter or add to an original frame resulting in an increase in height of the vehicle, or cause the vehicle body or chassis to come in contact with the ground, expose the fuel tank to damage from collision, or cause the wheels to come in contact with the body. No part of the suspension on a vehicle shall extend below the lowest portion of a wheel rim on the vehicle. A part of the original suspension system shall not be disconnected or modified to defeat the safe operation of the suspension system. This section does not prohibit the installation of heavy duty equipment including bumpers, shock absorbers, and overload springs within the limitations of this section, or the removal of a bumper when necessary to install a snowplow, lift ramp, or similar device while the device is in place and operational.

(6) This section shall not be construed to establish standards stricter than those formulated by the United States department of transportation for bumpers on a passenger motor vehicle sold within the United States.

(7) This section does not apply to a vehicle having a manufacturer's design which intrinsically precludes conformance with this section, a vehicle with a GVWR of 10,001 pounds or more, a vehicle designed to carry 16 or more passengers including the driver, implements of husbandry, or a road tractor, truck or truck tractor owned by a wood harvester or contractor and used exclusively in connection with wood harvesting and logging operations, or a vehicle which has an unaltered bumper or suspension system as supplied by the manufacturer. The operator of a vehicle cited for a violation of this section may assert as an affirmative defense that the vehicle in question, at the time of the violation, met original manufacturer's specifications for equipment which affected its bumper or frame height. The operator shall establish by a preponderance of this evidence the affirmative defense asserted pursuant to this subsection.

(8) As used in this section:

(a) "Bumper height" means the vertical distance between the ground and the highest point of the bottom of the bumper, as measured to a level surface when the vehicle is unladen with the vehicle tires inflated to the manufacturer's recommended pressure. If the bottom of the bumper cannot be determined due to vehicle design, the measurement shall be made from the lowest point on the rearmost portion of the rear horizontal bumper bar, or the vertical distance between the lowest point on the forwardmost portion of the front horizontal bumper bar, as measured to a level surface when the vehicle is unladen with the vehicle tires inflated to the manufacturer's recommended pressure.

(b) "Frame" means the main longitudinal structural members of the chassis of the vehicle as equipped from the factory or, for a vehicle with unitized body construction, the lowest main longitudinal structural members of the body of the vehicle.

(c) "Frame height" means the vertical distance between the ground and the lowest point on the frame, measured when the vehicle is unladen on a level surface at the lowest point on the frame midway between the front axle and the second axle on the vehicle with the vehicle tires inflated to the manufacturer's recommended pressure.

(d) "GVWR" means the original manufacturer's gross vehicle weight rating as defined in section 18b.

(e) "Multipurpose passenger motor vehicle" means a motor vehicle, other than a truck or passenger vehicle, designed to carry 10 passengers or less and constructed either on a truck chassis or with special features for occasional off-road operation.

(f) "Other motor vehicle" means any truck, multipurpose passenger motor vehicle, or other motor vehicle having a GVWR of 10,000 pounds or less, not including a passenger vehicle or motorcycle.

(g) "Passenger vehicle" means a motor vehicle with motive power designed to carry 10 passengers or less, or a van having a GVWR of 5,000 pounds or less, but not including a multipurpose passenger motor vehicle, motorcycle, or truck.

History: Add. 1978, Act 225, Eff. Mar. 30, 1979; Am. 1987, Act 19, Eff. Jan. 1, 1991; Am. 1991, Act 129, Eff. Mar. 30, 1992