The Ford-Utilimaster Flexible Fuel Vehicle is an American light transport truck model, designed as a mail truck for the United States Postal Service (USPS), which is its primary user. It was built as a partnership between Ford Motor Company, which supplied a stripped-down, right-hand drive Ford Explorer chassis and drivetrain, and Utilimaster, which built the aluminum body and integrated it with the chassis. The FFV can operate with either unleaded gasoline or E85 ethanol-blended fuel using the Ford 4.0 L Cologne OHV V6 engine.

A post van is a type of delivery vehicle that is used to transport post. Originally horse-drawn, most modern mail trucks are automotive vehicles.