Trump Says He Approved Rollback of US Fuel Economy Rules

President Donald Trump said on Sept 26 that he had approved new fuel economy standards for automobiles, rolling back stricter rules adopted under former President Joe Biden.¹³

Trump's announcement

In a social media post, Trump declared that the new standards would end what he described as Biden's mandate for electric vehicles, using the single word "TERMINATE."²

Trump contended that the revised rules would reduce car prices and prompt manufacturers to boost domestic manufacturing. He wrote, "These new Standards will take the waste out of building cars in America." He added that this means "LOWER PRICES, saving families thousands on a new, beautiful, and safe car — Far better than the Environmental Monsters that we were building heretofore."¹²

Trump also said manufacturers had approached him wanting to build in the country, stating, "Every Manufacturer, from General Motors to Ford to Stellantis, has called me wanting to build here, and now they can!"¹

Transportation Secretary Sean Duffy reposted Trump's announcement and wrote "COMING MONDAY," signaling a forthcoming formal announcement. Duffy had earlier indicated the finalized requirements would be considerably weaker than those set under Biden.¹²

Background on CAFE standards

The Corporate Average Fuel Economy (CAFE) program, created by Congress in 1975, mandates that automakers hit specific average mileage goals for the cars and light trucks they sell. Regulators have revised these requirements over time, generally pushing for greater vehicle efficiency.¹²

Al Jazeera reported that Biden-era regulations finalized in 2024 called for average fleet fuel economy to climb from 39.1 mpg to approximately 50.4 mpg by 2031. According to CNBC, car manufacturers would have needed to boost the mileage of cars and light trucks to about 50 miles per gallon within the same timeframe. Officials under Biden argued the policy would cut gasoline use and pollution while lowering drivers' costs at the pump.¹²

Al Jazeera noted the tougher rules aimed to spur domestic electric vehicle manufacturing and sales, prompting carmakers to increase EV output to comply with Biden's mandates. Trump had previously unveiled a December 2025 proposal calling for a fleetwide average of about 34.5 mpg for light-duty vehicles by 2031, a figure over 30 percent below the Biden administration's target.²

Al Jazeera further noted that Republicans in Congress eliminated EV consumer tax credits last year through Trump's legislation known as the One Big Beautiful Bill Act, adding that no federal law compels Americans to purchase electric vehicles or prohibits sales of gasoline-powered cars.²

Industry and policy implications

According to The New York Times, the updated fuel-economy rules would end a government push to accelerate the shift to electric cars, as the administration moves to dismantle clean-vehicle regulations.³

CNBC reported that looser fuel-economy requirements would let automakers manufacture more pickups and SUVs — vehicles that generate higher profits despite lower gas mileage — while diminishing the incentive for companies to build electric vehicles. Some companies, including General Motors, have said they will still make electric vehicles.¹

CNBC noted the shift would deliver on a Trump campaign pledge to undo policies that promoted or incentivized electric vehicle adoption. The precise contents of the finalized standards remain uncertain, since complete details have not been released by Trump or his administration.¹²