The CLS 63 AMG is a high performance variant of the CLS and went on sale in March 2011. It features a 5.5 L bi-turbo V8 rated at and . Standard equipment includes an
AMG SpeedShift MCT 7-speed transmission, a wider front
track, larger 360 mm ventilated and perforated brake discs, an AMG sports exhaust system, and a three-spoke AMG Performance steering wheel with shift paddles. The CLS 63 AMG is available in both sedan and Shooting Brake variants, as well as in rear-wheel drive or 4MATIC all-wheel drive configurations. Edition 1 models were available exclusively in the first year of its market launch, and featured power increases of and . Other additions include Edition 1 insignia, matte exterior paintwork, designo leather, and a choice of three AMG exclusive interior trim. An AMG Performance Package was also offered separately, and featured a carbon-fiber spoiler lip, red brake calipers, and increased performance gains of and , resulting in a 0– time of 4.1 seconds. From April 2013, the CLS 63 AMG range was updated to now produce and . The Performance Package was also replaced by the new CLS 63 AMG S model, featuring further performance and efficiency enhancements, all-wheel drive 4MATIC as standard, and a rear
locking differential. It is also available as a Shooting Brake variant and launched in June 2013. == Model year changes ==