TDI enables a fuel efficiency saving of up to 40% compared with conventional petrol engines in the USA. The aim of the Audi Mileage Marathon was to demonstrate the superior efficiency of diesel technology. The task: to drive 7,700 km across the USA – in 13 days. 184 drivers from 15 countries took part in 23 Audi models. So this was not just an excellent opportunity to show America the advantages of TDI technology; it also made for a fascinating road trip.