"Fuel economy is measured under controlled conditions in a laboratory using a standardized test procedure specified by federal law. Manufacturers test their own vehicles—usually pre-production prototypes—and report the results to EPA. EPA reviews the results and confirms about 10-15 percent of them through their own tests at the National Vehicle and Fuel Emissions Laboratory (NVFEL)."
Additional information about fuel economy and testing is available at:
- Fuel Economy, EPA’s Office of Transportation and Air Quality
- Data and Testing, NVFEL
- How Vehicles are tested, FuelEconomy.gov (Department of Energy and EPA)
- Many Factors Affect Fuel Economy, FuelEconomy.gov
The U.S. Department of Transportation (DOT) sets fuel economy standards for cars and trucks through the Corporate Average Fuel Economy (CAFE) program. The standards are for the average fuel economy of the entire fleet of cars or trucks for a given model year as opposed to a specific vehicle or model. A penalty is assessed if a manufacturer's fleet does not meet the average standard and are enforced by DOT.
For more information on CAFE, visit DOT's CAFE - Fuel Economy.
For information about the following issues to help keep your car in shape, see:
Driving efficiently and keeping your car in shape will make a difference.