As the S-class of Benz’s SUVs, the 2021 Mercedes GLS-class aims to deliver an undeniably upscale experience, and it succeeds. This large three-row SUV has room for the whole family and pampers everyone with its tech-rich cabin, comfortable ride, and fancy interior materials. Buyers can choose from either a 362-hp turbocharged inline-six or a 483-hp twin-turbo V-8, both of which benefit from a hybrid-assistance system. Despite that technology, neither powertrain provides very impressive fuel efficiency, but at least the GLS’s EPA ratings are in line with those of rival SUVs such as the Land Rover Range Rover and the Lincoln Navigator. All-wheel drive comes standard, as does an air suspension, but Mercedes offers a pothole-sensing upgrade that also increases ground clearance.
The GLS-class was new last year, so 2021 models see only a few changes. Four-zone automatic climate control, ventilated seats, and 20-inch aluminum wheels are newly standard. As is a parking-damage detection feature, which can alert an owner’s smartphone via the Mercedes Me Connect app if the car senses a collision while parked. The GLS450’s turbocharged inline-six provides plenty of power and is just as smooth as the GLS580’s V-8, so we’d stick with that and put the extra dough toward some options. The Executive Rear Seat Plus package turns the second row into a luxurious zone with massaging seats, a wireless smartphone charging pad, a tablet controller for the GLS’s infotainment system, plusher headrests, and side-impact airbags. Ordering that package requires that you shell out for leather upholstery, which, surprisingly, isn’t standard.
Two models are offered—the six-cylinder GLS450 and the eight-cylinder GLS580—and both feature some hybridization. The GLS450’s turbocharged 3.0-liter inline-six is silky smooth and good for 362 horsepower. The GLS580 is far more powerful, making 483 horsepower from its twin-turbocharged 4.0-liter V-8. Despite its size, the GLS-class is easy to hustle on a twisty road, but it’s not overly sporty or harsh over bumps. All models come standard with an air suspension, but Mercedes offers a trick new system called E-Active Body Control. It utilizes a forward-facing camera to scan for bumps and adjusts the suspension accordingly so riders won’t feel those road imperfections. It’s a cool technology but expensive, and we think most buyers will find the standard setup does a fine job.
The EPA fuel-economy estimates for the GLS-class aren’t great. The GLS450 earns 19 mpg in the city, 23 mpg on the highway, and 21 mpg combined. The GLS580 does worse, with 16 mpg, 21 mpg, and 18 mpg, respectively. In our real-world testing, the GLS450 performs a little better than its rating, managing 24 mpg on our 200-mile highway loop. The GLS580 returned a dismal 18 mpg in the same test. If fuel economy is a priority for you, the BMW X7 will be a better choice in the luxury-SUV department. A six-cylinder X7 xDrive40i managed an impressive 28 mpg in our highway test while an eight-cylinder xDrive50i delivered 24 mpg.
Borrowing its dashboard and cockpit layout from the similarly new GLE-class SUV, this generation of GLS is far more modern than the one it replaces. It’ll fit up to seven passengers but can be spec’d for six with the optional captain’s chairs. Passenger space is generous in the first and second rows, and the third row, while not as spacious as the second, can accommodate an adult without too much complaining—something that can’t be said of the wayback in the X7.