What we have here are two Sedans from Audi with some differences, such as the model year, powertrain, fuel economy, horsepower, and maximum occupancy. First of all, the 2013 A7 has a more powerful engine and gets 9 mpg less than the 2016 A6 Diesel. Also, the A6 Diesel seats one more passenger than the A7. Among similarities are the body structure, market segment, starting price, ground shadow size, and height.