The National Highway Traffic Safety Administration is investigating a series of complaints over Freightliner Cascadia trucks suddenly slowing due to an automatic emergency braking system.
The allegedly faulty system involves 2017–2022 trucks, potentially affecting approximately 250,000 vehicles made by Freightliner Trucks, a division of Daimler Truck North America. Drivers report activation of the AEB system “without an actual roadway obstacle,” a notice said, prompting an investigation to begin May 26.
The administration’s Office of Defects Investigation received 18 complaints from vehicle owners or drivers, where several said the vehicle will randomly slam on the brakes.
Some described how the issue arose when approaching bridges and overhead signs. Among the complaints, drivers said:
- “This system routinely signals an impending collision and applies the brakes, sometimes in a very aggressive way, for no reason whatsoever.”
- “The forward radar sensor detects a target 3 feet in front of me and slams on the brakes if the cruise control is set.”
- “Locked up the brakes in the rain causing a slide. Locked up on ice almost causing a jackknife. Then this summer it has locked up when nothing is around.”
Another driver said the adaptive cruise control and forward crash avoidance systems misinterpret data. And some operators suggested a third-party manufacturer was connected to the issue.
The complaints were filed over several years and involved a range of drivers, including those with over three decades of experience who voiced safety concerns.
When asked about the potentially faulty system, a Daimler Truck North America spokesperson said in a statement that the company "is fully committed to the development of life-saving technologies such as Automatic Emergency Braking.”
Editor’s note: This story has been updated to include a statement from Daimler Truck North America.