Four major truck manufacturers — Daimler, Volvo, Paccar, and International Motors (formerly Navistar) — have filed a lawsuit against California, seeking to block the state from enforcing strict emissions regulations that U.S. President Donald Trump declared invalid in June.
In a complaint lodged on Monday in the federal court in Sacramento, the companies argued they had been “caught in the crossfire” after Trump rescinded waivers granted during the Biden administration, which had allowed California to set its own emissions standards. The revocation included the state’s Clean Truck Partnership, a 2023 agreement aimed at boosting sales of zero-emission heavy-duty trucks and cutting nitrogen oxide emissions, while giving the industry flexibility to meet the targets.
The truckmakers said the reversal created regulatory uncertainty that has caused “irreparable harm”, preventing them from planning production and determining which vehicles could be sold. The lawsuit names the California Air Resources Board (CARB) and Democratic Governor Gavin Newsom as defendants. Neither Newsom’s office nor CARB responded to requests for comment on Tuesday.
Later that day, the U.S. Federal Trade Commission (FTC) announced it had ended an antitrust investigation into the Clean Truck Partnership. The FTC said Daimler, Volvo, Paccar, and International Motors had agreed to avoid future anticompetitive agreements with state regulators. “CARB’s regulatory overreach posed a major threat to American trucking,” Taylor Hoogendoorn, deputy director of the FTC’s Bureau of Competition, said in a statement.
Trump, a Republican, has moved to limit California’s authority under the federal Clean Air Act to impose pollution limits stricter than federal standards, as well as Governor Newsom’s ability to promote electric vehicles as part of the state’s climate strategy. Since 1970, California has received more than 100 waivers under the Act. In June, Trump also blocked the state’s plan to phase out sales of petrol-only vehicles by 2035 — a move California is now challenging in court.
The case is Daimler Truck North America LLC et al v. California Air Resources Board et al, U.S. District Court, Eastern District of California, No. 25-02255.
