12 740 miles per gallon

You read it right. That's the fuel efficiency reached by the Pac Car.

At 5385 km/l (12 740 miles / gallon), it holds the World record.

To learn more:

http://www.esoro.ch/english/content/kernk/nhanst/paccar/01paccar.htm#

http://www.paccar.ethz.ch/