With a sleek and distinct design as well as a host of AMG-specific enhancements, the 2021 CLS53 is a four-door coupe that is as elegant as it is athletic. Power comes from a silken, turbocharged, 429-hp, straight-six engine that’s mated to an astute automatic transmission and standard all-wheel drive. The CLS53 is nearly mechanically identical to the Mercedes-AMG E53 sedan, but due to its racier styling, its back seat and trunk are less accommodating. Its cabin boasts cutting-edge technology that effortlessly mingles with an assortment of upscale materials and finishes. While the CLS53 is better at long-distance cruising than backroad thrills, it has the ability to engage you when you activate its sportiest performance settings. The Audi S7 is both more exciting and practical, but the CLS53 costs less and looks more upscale.
What’s New for 2021?
For 2021, Mercedes installs an entirely new infotainment system in the CLS53. Called MBUX (short for Mercedes-Benz User Experience), the upgraded unit brings a new touchscreen and a responsive touchpad with haptic feedback. It also features a voice-activated assistant—think Amazon Alexa or Apple’s Siri—as well as innovative options. The latter includes navigation with augmented reality, which overlays guidance and other real-time information onto a live video feed of the road ahead that’s showing on the screen. The CLS53 also now has more advanced driver assists that can react to live-traffic data and stop the car from turning left if it detects oncoming traffic.
Engine, Transmission, and Performance
Every Mercedes-AMG CLS53 comes with a turbocharged and electrically supercharged 3.0-liter inline-six-cylinder engine with a 48-volt hybrid-assist system called EQ Boost, a nine-speed automatic transmission, and all-wheel drive. The engine is rated at 429 horsepower and 384 lb-ft of torque, with EQ Boost adding up to 21 horsepower and 184 lb-ft. The CLS53 we tested hit 60 mph in 4.0 seconds and covered the quarter-mile in 12.5 seconds at 111 mph. The inline-six is characterful and eager to rev, and the nine-speed delivers quick upshifts and satisfying downshifts. The AMG CLS53 is equipped with an air suspension and adaptive dampers as standard. This setup provides surefooted handling and an acceptable ride on most roads, but the CLS loses composure over bumps and can feel brittle over rough pavement. The similar E53 has slightly softer tuning and offers a more compliant ride as a result. We have no complaints about the CLS53’s electrically assisted steering, though. It’s direct and surprisingly rich in feedback.
Fuel Economy and Real-World MPG
According to the EPA, the CLS53 is rated for 21 mpg city and 26 mpg highway. In the real world, it appears to be more efficient than the government estimated, though the CLS53 returned 30 mpg on our 75-mph highway fuel-economy test route.
Interior, Comfort, and Cargo
Mercedes has a knack for integrating the latest technology into its interiors while preserving the old-world opulence that everyone expects in a luxury sedan from the brand. So it is with the CLS53. All the major displays are digital, including the instrument panel, which measures 12.3 inches, yet there’s a warmth to this four-door coupe’s cockpit that competitors can’t quite match. In the rear, the CLS53 feels more like a sedan than a coupe, with three-across seating and a 40/20/40-split folding rear seat. The sloped roofline reduces headroom for adults, however. The trunk capacity is only 12 cubic feet.