Two Sedans with more similarities, such as the body structure, market segment, ground shadow size, height, and maximum occupancy, than differences, like the powertrain, fuel economy, starting price, and horsepower. First of all, the 2015 Cadillac CTS has a more powerful engine and gets 7.7 mpg less than the 2016 BMW 5 Series Diesel. Also, there is a $12,005 difference in the base MSRP. The 2016 5 Series Diesel has a higher starting price than the 2015 CTS. Among similarities are the body structure, market segment, ground shadow size, height, and maximum occupancy.