The 2020 Mercedes-Benz GLS-Class SUV puts a pitch-perfect marker down on ever-bigger SUVs—and on opulence.

It arrives late this year just in time to defend its turf from a slew of ultra-luxury SUVs, not to mention the naff Lincoln Navigator and the new BMW X7.

The 2020 GLS wears a new look that owes much to the softer shape of the mid-size 2020 GLE-Class SUV; the GLS-Class is essentiallly the long-wheelbase version of that vehicle. The GLS’ longer body resolves the angular looks of the previous version into a more pleasantly rounded and tapered shape. Its LED headlights frame a wide twin-ribbed grille and its enormous three-pointed star—lit for emphasis, of course—while LED taillights arrow in from the tailgate’s corners. Mercedes says the 2020 GLS has been aerodynamically tuned for better fuel economy and for less wind noise, and it shows.

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The cabin adopts twin 12.3-inch screens for the gauge cluster and the central interface. Its bright metallic surround and the shape of the air vents mimic the outline of the GLS itself. Ambient lighting runs in a ribbon across the dash and outlines the driver and passenger grips that double as armrests on the center console.

With the GLS, Mercedes boosts power and economy with a pair of mild-hybrid powertrains. The larger of the two is a new 4.0-liter twin-turbo V-8 with a 48-volt mild-hybrid system that integrates a starter-generator to reduce fuel consumption. In the 2020 GLS580, it’s rated at 483 horsepower and 516 lb-ft of torque, its so-called “EQ Boost” mild-hybrid pack adds up to 21 hp and 184 lb-ft of additional power. Benz quotes a 0-60 mph time of 5.2 seconds and a top speed of 130 mph.

The junior GLS450 repurposes the 3.0-liter turbo inline-6 that’s now made its way into various CLS-Class and E-Class models. With 362 hp and 369 lb-ft of torque, it’s good for a 0-60 mph run of 5.9 seconds and a 130-mph top end—and it’s fitted with the same mild-hybrid technology.

A 9-speed automatic shifts power in both versions, as does a new all-wheel-drive system that uses a multi-plate clutch to transfer power between axles. On the GLS580, an optional transfer case and low-ratio gear work in concert with the transmission and engine controls to distribute power not just for off-road traction, but for improved grip on pavement.

Electric power steering and an air suspension with adaptive damping are standard on both models. The suspension can be fitted with a system that uses cameras to read road conditions and adapt each wheel’s damping individually. The setup can counteract body lean with stiffer damper pressure, or can soften the air springs in advance of a large bump in the road. The suspension can even help the GLS to “rock” itself out of difficulty, in sand dunes or in mud, by pushing individual wheels up or down to create better traction.

Bigger and plusher

The 2020 GLS-Class takes no chances in losing the upsizing wars. It’s grown to 205.0 inches long as a twin-turbo V-6 GLS450, 205.2 inches as a twin-turbo V-8 GLS580. The wheelbase is up by 2.4 inches to 123.4 inches for a more spacious second- and third-row seating package—somehow, Benz says it’s freed up to 3.4 inches more in the second row, which makes a future Maybach edition all the more plausible. A second-row bench can be swapped out for a pair of captain’s chairs; an executive package gives those individual seats a tablet that can control the car’s entertainment and climate controls, from the audio system to a live Web browser.

All three rows of seats can be power-adjusted, and both the second and third rows can fold flat at the touch of a single button to boost cargo space. The third-row seat promises adult-size space, seat heating, and its own USB ports. Mercedes hasn’t released specs for interior volume though.

Safety features for the 2020 Mercedes GLS include available adaptive cruise control with traffic-jam assist that cuts vehicle speed as it approaches accidents detected by real-time traffic data, and can maintain stop-and-go control of the car’s acceleration and braking up to 37 mph. Blind-spot monitors and surround-view cameras come standard.

The gesture-sensitive center screen can recognize driver from passenger, for easier seat adjustments and other functions that can be changed while the car is in motion. The infotainment has a voice assistant that can predict when drivers usually ask for some functions such as radio stations and phone calls at certain times.

Other available or standard features include power features, wireless smartphone charging, second-row massaging seats, five-zone automatic climate control for the GLS580  (an option on the GLS450), a head-up display, Burmester audio, up to 9 USB ports, Apple CarPlay and Android Auto compatibility, ambient lighting, heated and cooled cupholders, multi-contour front seats, an in-car fragrance dispenser, and open-pore wood trim. A panoramic roof is available, as are wheels from 19 inches up to 23 inches. A car-wash button closes all windows and folds the mirrors and displays front-end camera information while the GLS rolls in for a bath.

The 2020 Benz GLS goes on sale later this year, but EPA gas mileage and price haven’t been confirmed. It’s assembled in the same Tuscaloosa, Alabama, plant where the GLE-Class calls home.