Two Sedans with some similarities, but otherwise different in most aspects such as the model year, powertrain, market segment, horsepower, fuel economy, and ground shadow size. First of all, the is a newer vehicle by 3 model years. Also, a bigger engine usually means less mpg. But the 2013 3 Series Sedan Hybrid has a more powerful engine and it gets 4.4 more mpg than the 2016 CTS. In addition, the body structure of 3 Series Sedan Hybrid is slightly smaller than that of the CTS. Among similarities are the body structure, market segment, starting price, height, and maximum occupancy.