The Trump administration finalized new vehicle fuel economy standards on Monday, September 28, 2026, lowering the requirements for automakers. The Transportation Department established a fleetwide average of 34.9 miles per gallon (mpg) to be achieved by 2031. This decision reverses a policy from the Biden administration that had aimed for a fleetwide average of 50.4 mpg by the same year.
The move follows a period of rising fuel costs for U.S. drivers, which the source noted has been influenced by a conflict between Israel and Iran that began in late February. The administration stated that the new standards are intended to make it easier for companies to sell gas-powered vehicles. According to the department's own estimates, the lower standards will reduce the cost of new vehicles but will also lead to higher fuel consumption and increased carbon dioxide emissions over the coming decades.
The Alliance for Automotive Innovation, representing major manufacturers including General Motors, Toyota, Volkswagen, Hyundai, and Ford, spoke in support of the change. The trade group stated that the government made the correct decision to align standards with market conditions, arguing that the previous Biden-era rules effectively required a transition to electric vehicles that was out of step with market realities and customer demand. Conversely, the Sierra Club announced it would challenge the rollback, stating that the policy grants automakers a "free pass on pollution" while shifting costs to families through higher fuel bills and health impacts.
The environmental impact of this policy shift is expected to be felt over several decades through increased carbon dioxide emissions, as reported by the department's own analysis. By reversing the 2024 Biden-era rules—which required annual efficiency increases of 8% for model years 2024-2025, 10% for 2026, and 2% annually thereafter—the new rule sets a lower trajectory for automotive technology. The trade group representing major automakers indicated the previous rules were pushing an EV transition faster than customers were prepared to follow.
What happens next involves both legal and industrial transitions. The Sierra Club has stated its intent to fight the rollback. For automakers, the finalized 34.9 mpg target provides a compliance benchmark for their production cycles through 2031. While the lower standards are now finalized as of September 28, 2026, the specific dates for court challenges or further legislative oversight were not reported. Drivers will likely see the impact on vehicle pricing as the new standards take effect.