Although most states’ truck lighting requirements coincide with Federal Motor Carrier Safety Regulations (FMCSR) issued by the Federal Department of Transportation, some do not, and others only are required to match federal laws when the loaded (gross) weight of the vehicle reaches certain weight limits. Generally, if a truck is not used for Interstate commerce and weighs in, loaded, below 10,000 pounds, the lighting requirements and regulations of the individual state are followed.
General Truck Lighting
FMCR rules require standardization of color and placement of lights and reflectors for all commercial vehicles involved in Interstate commerce. Both low and high beam headlights must be white and mounted symmetrically 22 to 54 inches from the ground. Parking lamps can be white or yellow and mounted symmetrically on the front of the truck as far apart as possible. Front turn signals must be yellow and mounted as far apart as possible. Rear turn signals must be red or yellow and indicate the direction of the turn. Three front identification lamps are required to indicate the presence of a wide vehicle. Trucks must have two red rear side marker lamps to indicate the width. Trucks must have two each of red clearance lamps, identification lamps, tail lamps and stop lamps on the rear of the truck. One white license plate lamp is required. If a truck is less than 80 inches high, it must have a center-mounted stoplight mounted in the center of the top and rear of the truck.
FMCR also requires that trucks must have yellow reflectors marking the front and center of the vehicle. Two rear side red reflectors should be mounted on each side at the rear of the vehicle, back as far as possible facing the sides and a minimum of 15 inches high. Reflectors on the rear of the truck should be mounted as far apart as possible facing the rear at a height of 15 to 60 inches.
Lighting for truck tractors
Another FMCR requirement states that truck tractors have two pairs of white rear upper-body marking lights mounted as high as possible. Rear marking lights must be facing to the rear mounted on the fenders or mud flap brackets. The rear marking lights must not be any higher than 5 feet off the ground. Front and side lighting requirements remain the same as other truck lighting.
Lighting for Long Vehicles
Long truck FMCR rules require vehicles longer than 30 feet have additional lights and reflectors. A long truck must have a minimum of two yellow lights on each side near the center. To warn of the presence of a long truck, there must also be a minimum of two yellow side reflectors mounted 15 to 60 inches from the ground facing sideways.
FMCR Rules for Lighting for Tow Vehicles
Vehicles that work in a drive-away/tow-away operation must have at least two front headlights spaced equally apart on each side of the front. It must also have turn signals on the front and one clearance lamp on each side. There must be at least one side marker lamp near the front on each side of the towing truck. There must also be two turn signals, two stop lamps and two tail lamps on the rear. The rear of the vehicle must be marked with a side marker lamp. For towing vehicles that are more than 80 inches wide there must be three identifications lights on the rear.