EPA Proposes Rescinding Endangerment Finding and All Truck Greenhouse Gas Standards
The July 29, 2025, proposal would repeal every federal GHG standard for medium- and heavy-duty vehicles and engines, including the Phase 3 rule finalized in 2024.
Environmental Protection Agency Administrator Lee Zeldin on July 29, 2025, released a proposal to rescind the agency's 2009 Endangerment Finding, the determination EPA has relied on to regulate greenhouse gas emissions from new motor vehicles and engines. Zeldin announced the plan at an Indianapolis truck dealership.
If finalized, the proposal would repeal all greenhouse gas standards for light-, medium- and heavy-duty vehicles and heavy-duty engines, going back to the first truck and engine standards set in 2011. That includes the Heavy-Duty Greenhouse Gas Phase 3 rule finalized in 2024.
EPA's reasoning
EPA said that without the finding, it would lack authority under Section 202(a) of the Clean Air Act to set greenhouse gas standards for vehicles. The agency said the proposal would save Americans $54 billion a year in costs and cited Supreme Court decisions, including Loper Bright Enterprises v. Raimondo and West Virginia v. EPA, as narrowing its authority. It also cited a Department of Energy climate report released for comment at the same time.
"With this proposal, the Trump EPA is proposing to end sixteen years of uncertainty for automakers and American consumers," Zeldin said.
EPA said it would open a public comment period, with details to be published in the Federal Register.
Trucking groups applaud
"We commend President Trump and EPA Administrator Zeldin for taking decisive action to rescind the disastrous GHG Phase 3 rule," said American Trucking Associations President Chris Spear. "This electric-truck mandate put the trucking industry on a path to economic ruin and would have crippled our supply chain, disrupted deliveries, and raised prices for American families and businesses."
OOIDA President Todd Spencer said small-business truckers "could be regulated out of existence" under Phase 3. "Mom-and-pop trucking businesses would be suffocated by the sheer cost and operational challenges of effectively mandating zero-emission trucks," he said.
Clean Freight Coalition Executive Director Jim Mullen also welcomed the step, Transport Topics reported, and Indiana Motor Truck Association President Gary Langston attended the event.
Opponents included the U.S. Climate Alliance, a group of 24 governors. "Greenhouse gas pollution causes climate change and endangers our health and welfare — period," the alliance said, according to TT.
What it means for drivers and fleets
Phase 3 standards were scheduled to begin phasing in with model year 2027 trucks, and manufacturers and fleets had been planning around them. The proposal signaled that those carbon dioxide limits, and the earlier Phase 1 and Phase 2 greenhouse gas rules, could disappear, easing pressure to buy battery-electric or hydrogen trucks. It was still only a proposal, subject to public comment, so truck makers and fleets faced continued uncertainty in their equipment planning.