The CLS features a trademark coupe-like silhouette that still manages to incorporate sedan-like four doors. The CLS550 and CLS550 4MATIC (all-wheel drive) are equipped with a 402-hp biturbo 4.6-liter V8 engine. The more aggressive CLS63 AMG has a 518-hp 5.5-liter biturbo V8 (550-hp with the AMG Performance Package). A seven-speed automatic transmission with sequential shift capability sends power to the rear wheels. All models are equipped with Mercedes-Benz's Pre-Safe system, which will automatically close the sunroof and move the front seats to the safest position if sensors automatically detect an impending collision. More traditional safety features such as side-curtain airbags and anti-lock brakes also come standard. As expected from Mercedes, luxury appointments abound. With features like power front seats, four-zone automatic climate control, six-disc satellite surround sound audio, and doors that shut themselves if you forget to, comfort and convenience are everywhere. The CLS have been completely redesigned inside and out for 2012. The CLS550 4MATIC (all-wheel drive) model has been added. New engines are now in use.