Two Sedans with some similarities, but otherwise different in most aspects such as the model year, powertrain, modifications, market segment, horsepower, and fuel economy. First of all, there is a difference in model years. The is 3 years newer. Also, the 2016 CLA-Class AMG CLA 45 has bigger and thirstier engine; the 2013 3 Series Sedan Hybrid gets 2 more mpg. Among similarities are the body structure, market segment, starting price, ground shadow size, height, and maximum occupancy.