The Audi Q7 TDI mileage has made a significant improvement between the 2010 model and the 2011 model. The 2010 model was definitely a gas-guzzler, but the 2011 model has cleaned up its act and is one of the most fuel-efficient cars in the luxury midsize SUV category. In the city, the 2011 Audi Q7 TDi offers a gas mileage of 17mpg and on the highway is offers a gas mileage of 25.The price of this model, however, has been increased by $4000 compared to the previous 2010 model which offered gas mileage of 13 in the city and 18 on the highway.