California has finalized the repeal of major zero-emission vehicle mandates targeting heavy-duty commercial fleets.
The California Air Resources Board (CARB) has formally rolled back the High Priority and Drayage Fleet requirements under its Advanced Clean Fleets (ACF) rule. The repeal took effect on September 10, 2026, following formal approval from California's Office of Administrative Law (OAL).
The move concludes a years-long legal battle spearheaded by the California Trucking Association (CTA). The industry group filed a federal lawsuit against CARB on October 16, 2023, challenging the state's aggressive timeline requiring commercial fleets to transition to zero-emission heavy-duty trucks.
In its lawsuit filed in the U.S. District Court for the Eastern District of California, CTA acknowledged that “CARB's efforts are in service to the laudable goal of decreasing tailpipe emissions from commercial vehicles,” but added that the ACF regulations “represent a vast overreach that threatens the security and predictability of the nation's goods movement industry.”
The lawsuit received support from the Owner-Operator Independent Drivers Association and the American Trucking Associations.
CTA secured an advisory letter in late December 2023 in which CARB agreed to withhold enforcement of the fleet rules pending approval of a federal Clean Air Act waiver request by the U.S. Environmental Protection Agency. By April 25, 2025, negotiations between CTA and CARB produced an agreement to repeal the provisions.
With the OAL’s formal approval now in place, CTA said it is coordinating with legal counsel on final steps to formally settle the ongoing litigation. The association characterized the outcome as a major victory for its members and commercial operators across the state.
