Flashing brake lights still an option
The Federal Motor Carrier Safety Administration (FMCSA) has given new life to an exemption allowing motor carriers to install pulsating brake lights on their commercial trailers and van-body trucks.
First issued in 2020, the exemption lets companies install brake-activated pulsing lights from Grote Industries in one of five configurations. Grote says over 80,000 vehicles are now equipped with the pulsing lights, and results are promising:
- One large national fleet customer reported a 33-percent reduction in overall rear-end crashes on a per-mile basis compared to a baseline fleet without the system installed, and a 75-percent reduction in crashes involving personal injuries.
- Another large fleet customer reported similar outcomes, noting a 52-percent reduction in overall recordable incidents per vehicle and a 75-percent reduction in the severity of incidents that did occur.
Allowable configurations
Under the exemption, the pulsating lights may be added to any trailer or van-body straight truck, in addition to the normal steady-burning brake lamps. The only catch is that they must pulsate in an amber color for only four seconds before turning red and burning steadily until the brakes are deactivated.
The allowable configurations are as follows:
- Upper pair: Two lamps centered at the upper rear, positioned 6-12 inches from the centerline of the outermost identification (ID) lamps, and in line with the three-ID-lamp cluster.
- Single lower lamp: One lamp centrally located on or below the rear sill, in line with the stop/tail/turn lamps.
- Upper pair + single lower lamp: A combination of the three lamps described above.
- Lower pair: Two lamps centered at the lower rear, located on or below the rear sill.
- Upper pair + lower pair: Both the upper pair and the lower pair as described above.
The exemption was reissued on November 17, 2025, and is set to last through 2030.
Tank trailers
The FMCSA recently renewed a similar exemption for tank trailers, though with restrictions on where the lamps may be placed. The pulsating lights — either amber or red — must be located in the upper center position or in an upper dual outboard position on the rear.
This exemption, granted to National Tank Truck Carriers, Inc., was reissued on November 17, 2025, and is in place until October 2030.
Rear-end crashes generally make up about 30 percent of all crashes, the FMCSA says, and large trucks are three times more likely than other vehicles to be struck in the rear in two-vehicle fatal crashes.
Key to remember: Motor carriers have the option to install pulsating brake lights on all commercial trailers and van-body straight trucks, with certain restrictions, as a way to prevent rear-end collisions.





























































