Major automakers including General Motors, Toyota, and Volkswagen have backed the Trump administration against a legal challenge by California and other states, supporting the rollback of fuel economy rules. The US Department of Transportation is finalizing a fleet-wide fuel economy average of 34.9 miles per gallon (14.8km per litre) by 2031, a reduction from the 50.4 miles per gallon (21.4km per litre) approved by former US President Joe Biden in 2024. Regular petrol averaged $4.17 per gallon (3.78 litres) on Monday, October 31, 2026, according to the American Automobile Association.