2019 Mercedes-Benz CLS-Class

The car that created the upscale auto industry’s current craze for four-door coupes moves into its third generation for 2019 with a new design the automaker says “fully embodies the next stage of the Mercedes-Benz design language,” while carrying forward the “timeless appeal of the original CLS.”

Benz says the new CLS is longer and wider and rides on a stretched wheelbase, changes that allowed its engineers to create a more spacious cabin that emphasizes the car’s newfound width. That is especially obvious in the rear seat, where a three-place bench replaces the outgoing car’s two-seat configuration; that also allowed Benz to install a more flexible folding seat arrangement that splits 40/20/40.

This reimagined CLS brings a new challenge to four-door coupe competitors like the BMW 6 Series Gran Coupe and the Audi A7. The main difference between the CLS and those cars is the Benz’s use of a traditional trunk, whereas BMW and Audi fit their respective models with a more practical fast/hatchback cargo opening. Both are more than competent performance cars, but neither can boast the same level of high-tech chutzpah under the hood.

The 2019 CLS becomes the first Benz whose engine lineup -- at launch, at least -- consists exclusively of mild hybrid engines based on the company’s new 48-volt electrical system. Both CLS 450 and AMG CLS 53 models share a turbocharged 3.0L inline six-cylinder gasoline engine with an integrated electric motor.

On its own, the engine makes 362 hp and 369 lb-ft of torque in the CLS 450 and 429 hp/384 lb-ft for the CLS 53, and the mild hybrid system adds 21 hp and 184 lb-ft to those figures when the driver requests full power. On both engines, the 48-volt electrical system also runs the water pump, while a secondary traditional 12-volt setup provides power for lighting and in-cabin controls.

In both engines, the hybrid drive system uses regenerative braking to direct electricity back to the car’s battery in deceleration; it also allows for what Benz calls “silent start,” and can shut the engine off when coasting to a stop at a red light.

Both versions of the new CLS use a nine-speed automatic transmission; the AMG CLS 53 boasts a “speedshift” version of it, along with a more sophisticated version of the brand’s 4Matic all-wheel drive system.

Standard kit in CLS 450 models includes 19-inch wheels, leather upholstery, heated front seats with memory, heated steering wheel, adaptive damping, sunroof, garage door opener, power-folding side mirrors, multi-colour ambient lighting, 12.3-inch infotainment display with touchpad, Apple CarPlay and Android Auto smartphone integration, automatic climate control and wireless phone charging.

The entry-level trim also gets advanced safety features like blind spot monitor, active brake assist, active park assist and heated windshield washers.

AMG CLS 53 trim adds the upgraded drivetrain, plus AMG styling cues inside and out.

Mercedes-Benz had yet to publish fuel consumption figures when we were writing this buyer’s guide article.