2019 Mercedes-Benz CLS 450, CLS 53 Review: Mercedes Maintains the Magic

Sunny Spain, with its winding roads up the serrated Montserrat mountains surrounding Barcelona, was a perfect place to gauge the latest Mercedes-Benz CLS. It’s a chance to sample the four-door coupe’s performance and handling, appreciate the exhaust notes from the new inline-six, and welcome an expanded lineup that now includes the first Mercedes-AMG CLS 53. A short rain shower seemed cued up to showcase the all-wheel-drive system, as well.

It was an opportunity to see if the third-generation CLS can hold court in the segment it created when it showed the first concept at the Frankfurt auto show back in 2003. Despite the apparent contradiction of the idea of a “four-door coupe,” since then, the world has become enamored with the idea of coupelike lines overlaid on sedan structure. The body style has resonated with 375,000 CLS buyers around the world and has spurred competitors to create their own four-door fastbacks. Mercedes even trumped itself at this year’s Geneva auto show, where it unveiled the even sexier Mercedes-AMG GT four-door coupe.

But the German carmaker has not forgotten that the CLS started it all. For the 2019 model year, the CLS family gets a new and cleaner design, new engine portfolio, and hybridization with a new 48-volt system that the automaker sees as a crucial next step in an automotive world that is becoming increasingly electrified.

At launch there are new 3.0-liter inline-six engines: a gasoline and a diesel. The U.S. only gets the gasoline version, which generates 362 hp and 369 lb-ft of torque in the CLS 450 but which also has the EQ Boost mild-hybrid system and 48-volt electrical system.

After launch, Mercedes is adding a 2.0-liter four-cylinder gas engine with a belt-driven starter alternator and 48-volt system—but it is not for the U.S., either. There are no specs yet, but officials say it will produce more than 300 hp.

The CLS 53 ups the performance to 429 hp and 384 lb-ft out of the I-6 by adding a twin-scroll turbocharger and an electric auxiliary compressor that builds boost until the turbocharger kicks in. Voila, no turbo lag. Acceleration is not neck-snapping but it is quick for a two-ton sedan: Mercedes claims it will do 0–60 mph in 4.5 seconds. Smooth, too.

For the CLS 450, Mercedes combines the starter and a generator in an electric motor positioned between the engine and transmission. The extra 22 hp and 184 lb-ft helps ensure power is at the ready and eliminates any lag before the twin-scroll turbocharger kicks in. The electric supercharger in the CLS 53 makes it even quicker off the mark, but again the power delivery is very linear. The other advantage is a seamless start/stop—we never felt the engine turn on or off—and the ability to “sail” when the engine disconnects from the transmission and coasts.

The motor also feeds the 1.0-kW-hr lithium ion battery. The 48-volt system can deliver four times the power of a standard 12-volt system at the same level of current (and hence wiring size). The CLS has an electric water pump and AC compressor.

On the CLS 450, the optional 4Matic all-wheel-drive system features a fixed 31/69 split of power between front and rear, and the CLS 53 has the standard 4Matic+ system to constantly adjust torque to wherever it is needed.

The multilink suspension comes with steel springs with a choice of optional adaptive damping or the air suspension system, which is standard on the 53. Drives modes are what you’ve come to expect—Comfort, Sport, and Sport plus—and although responsiveness improves with sportier settings, the difference is barely perceptible unless you are going quite fast.

The underhood soundtrack in the AMG is full of hits, starting with the satisfying crescendo of a straight-six accelerating and adding a symphony of snorts, pops, and gurgles on the downshifts. That’s music to any driver’s ears.

The nine-speed snicks up and down seamlessly. Smooth best describes the shifting, steering, and braking. The brakes never grab, and they respond as if they are reading the driver’s mind—especially in a groove on a winding road with nonstop twists and switchbacks, all of which the brakes handle with a sublime effortlessness.

Like the S-Class above it, the CLS has a suite of safety and driver-assist technologies to steer, accelerate, and brake as conditions demand. And like the Tesla, it can make a lane change by merely clicking the turn signal.

The ultimate nanny is the Distronic route-based cruise control, which adjusts speed to the legal limit and also reads preprogrammed data about the road ahead to keep you from barreling into a curve or roundabout. The first time you experience the vehicle slowing itself can be disconcerting, especially when you stomp on the accelerator and nothing happens. It is unusual to find a driver-assist features that cannot be overridden by manual actions. In this case the system ignores your frantic foot on the gas pedal. You must first tap the brake to disengage the safety system and allow you to resume control of your speed again. And of course, the feature can be turned off.

Mercedes has played with design since the original C219 slotted between the S-Class and E-Class, changing for the second-generation W218 in 2011. This third generation has a cleaner, simpler, and arguably meaner look—with a shark nose angled down and chrome twin-blade radiator grille that used to be reserved for AMGs with a V-8. Engineers have deemed the new I-6 worthy of the design cue.

For this generation, designers worked to reduce excess lines. The result is a sleeker and more elegant overall look. Gone are the previous generation’s blocky hips over the rear wheels. The front fascia’s flat headlamps have been updated, and there is a splitter in front and functional spoiler in back. The CLS 53 has an air curtain in front and round quad exhaust pipes in back. The license plate has been fitted into the rear bumper, and there is a two-piece rear tailllamp for the first time.

The CLS has a high shoulder line; combine that with a thick A-pillar and the raked windshield, and shorter drivers will battle a noticeable blind spot—making twisting mountain roads more adrenaline-filled than desired. But the high shoulders and narrow greenhouse make for a sumptuous side profile. Engineers claim its drag coefficient of 0.26 is the best in the segment.

The interior is more spacious with a modern luxury feel, and the mood is set with 64 colors of ambient lighting running across the dash and continuing along the door panels. The turbine-finned air vents are now illuminated, as well, and turn red when you turn up the heat and blue when you turn it down.

The 2019 model was designed as a true five-seater, with a bench in the back. But there’s no getting past the fastback roofline, which challenges taller passengers. The only concession is the combination of a wider vehicle and slimmer seats, which provides more legroom. Conversely, the new AMG GT will only be offered as a four-seater in the U.S. (but as a five-seater in Europe; guess Americans gotta lay off the chili cheese fries).

The CLS has a choice of beautiful materials, including optional Nappa leather seats with carbon-fiber trim, and sport seats for the 53. This is Mercedes, after all, so the seats are heated and cooled and offer a choice of massage sensations, from relaxing to stimulating. Turn on the active seat function to apply side bolsters as needed during a spirited ride. The 53 has the AMG performance flat-bottom steering wheel.

For infotainment, the CLS follows other Mercedes offerings with a pair of 12.3-inch screens under a single cover of glass to provide an array of data about the car and your trip.

The 2019 CLS 450 and CLS 53 will go on sale this fall in the U.S. Pricing has not been announced but should start just below $80,000 and stretch up to $100,000.