Volkswagen's 2013 Passat TDI is the most efficient diesel vehicle currently on sale.

Its EPA-rated figures of 31 mpg city, 43 highway and 35 combined put it above a throng of other Volkswagen-Audi diesels, and make it a prime choice for frugal highway driving.

But is 68 mpg within reach? If you're multiple economy record holder Wayne Gerdes, it might be.

In conjunction with Volkswagen of America, serial hypermiler Gerdes has set off on a 8,000-mile journey around the 48 contiguous states to set a Guinness World Record for "lowest fuel consumption--48 U.S. states for a non-hybrid car."

To set that record, Gerdes and the Passat will have to beat the previous record, already held in the Passat TDI, of 67.9 mpg.

"It’s going to be a great adventure and I’m confident we can improve upon the current record," Gerdes said.

With the journey already underway--Gerdes set off on June 7th from VW of America's Hernden, VA headquarters--Gerdes and co-driver Bob Winger will comfortably exceed VW's claims for 795 highway miles on every tank of diesel--already impressive range for a passenger vehicle.

Gerdes is certainly the right man for the job. In addition to holding the equivalent 48-state record in a hybrid vehicle, he's set over 100 other economy records.

That hybrid record was set just one year ago, by Gerdes and co-driver Chris Bernius in a 2012 Kia Optima Hybrid sedan, with a final figure of 64.5 mpg.

Such figures are beyond the reach of many drivers, and we'd usually not advocate the sort of ultra-efficient driving required to achieve such numbers--some hypermiling techniques can disrupt traffic or even be dangerous, though we're sure Gerdes is experienced in that regard.

But it does show that almost any vehicle is capable of more than its advertised figures, with careful driving.


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