This first-generation restyling of the Mercedes CLS is the four-door Fastback to consider if you want the original CLS look with later refinements. It remains a sleek grand tourer rather than a conventional sedan.
Gasoline Mercedes CLS engine pairings in this restyling Fastback use an automatic transmission and rear-wheel drive. Compare examples such as the CLS300 3.0 AT, CLS350 3.5 AT and CLS350CGI 3.5 AT and you mainly change displacement and injection, not the basic powertrain layout.
Mercedes CLS trim levels describe equipment packages on a given technical version, not a different drivetrain. On the CLS300 3.0 AT Fastback, you can choose CLS 300 or Special Series, so cabin features and styling details change while the gasoline automatic rear-wheel-drive layout stays put.