Two Sedans with more similarities, such as the body structure, market segment, starting price, ground shadow size, height, and maximum occupancy, than differences, like the model year, powertrain, fuel economy, market segment, and horsepower. First of all, there is a difference in model years. The is 3 years newer. Also, the 2013 3 Series Sedan Hybrid has a more powerful engine than the 2016 S4, but it gets 7.5 more miles on a gallon of fuel. Among similarities are the body structure, market segment, starting price, ground shadow size, height, and maximum occupancy.