Two Sedans with some similarities, but otherwise different in most aspects such as the powertrain, horsepower, starting price, fuel economy, and maximum occupancy. First of all, the 2016 Mercedes-Benz E-Class Sedan has a more powerful engine and gets 6.5 mpg less than the 2015 Audi A6 Diesel. Also, there is a $5,600 difference in the base MSRP. The 2015 A6 Diesel has a higher starting price than the 2016 E-Class Sedan. In addition, you'll seat two more passengers in the E-Class Sedan than in the A6 Diesel. Among similarities are the body structure, market segment, ground shadow size, and height.