The Mirror's Health , Lifestyle and Fashion

In 2015, two men drove a car through all 48 contiguous U.S. states on less than $300 of diesel fuel, or just eight tankfuls.

During the 8,233 mile trip they achieved a fuel economy of 81.17 miles per gallon, or 2.89 liters per 100 km.

They trounced the official rating for the car they used -- a VW Golf TDI rated by the EPA for 31 and 45 mpg in city and highway driving respectively -- earning a world record.

How did they do it? By applying a technique know as 'hypermiling,' which anyone can use to slash their fuel consumption, no matter which car they drive.

'Tutelage and inspiration'

The two drivers, Wayne Gerdes and Bob Winger, weren't new to this: they had, in fact, beaten their own previous record of 77.9 mpg obtained on the same route in 2013.

The very term 'hypermiling' was coined by Gerdes in 2004, and it became the Oxford Word of the year in 2008.

"I defined it is simply as beating the EPA in whatever yo