Washington State Bumper Law
Bumpers: A special motor vehicle shall be equipped with a bumper on both the front and rear of the vehicle with the exception of motor vehicles where the original or predominant body configuration, provided by a recognized manufacturer, did not include such bumper or bumpers in the design of the vehicle. For the relevant model year, bumpers must accommodate recognized manufacturer impact absorption systems per applicable Society of Automotive Engineers (SAE) Bumper Standards or equivalent standards.
Bumpers are optional equipment on vehicles defined as street rods and kit vehicles by the Washington state patrol vehicle inspectors.
Bumpers, unless specifically exempted above, shall be at least 4.5 inches in vertical height, centered on the vehicle's centerline, and extend no less than the width of the respective wheel track distances. Bumpers shall be attached to the vehicle in a manner equivalent to the original manufacturer's installation. Bumpers shall be horizontal load bearing and attach to the vehicle frame to effectively transfer energy when impacted.
The maximum bumper heights will be determined by weight category of gross vehicle weight rating (GVWR) measured from a level surface to the highest point on the bottom of the bumper. For vehicles exempted from the bumper requirement for the reasons stated above, a maximum frame elevation measurement shall be made to the bottom of the frame rail. Maximum heights are as follows:
Front
Back
Passenger Vehicles
22 Inches
22 Inches
4,500 lbs. and under GVWR
24 Inches
26 Inches
4,501 lbs. to 7,500 lbs. GVWR
27 Inches
29 Inches
7,501 lbs. to 10,000 lbs. GVWR
28 Inches
30 Inches
Adding an additional bumper will not meet the above requirements.
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