2020 Mercedes-Benz GLS Has Impressive Moves for a High-Tech Palace on Wheels
Benz's fully redesigned three-row luxury SUV balances loads of technology and solid driving character to be the (rich) parent's co-conspirator.
12/2/19 UPDATE: This review has been updated with test results for the GLS450 4Matic.
The 2020 Mercedes-Benz GLS-class is for all the parents out there. If you're young, flush with cash, and want to be seen in a big, expensive SUV, Mercedes will be happy to put you in a Post Malone–approved G-wagen.
HIGHS: Smooth operator, unexpectedly good handling, indulgently roomy.
The restrained three-row GLS is instead a triumph of substance over style. It's also an undercover co-conspirator to the driving-enthusiast parent. Picture yourself on a long road trip in your GLS. Your spouse and offspring are along, all dozing comfortably. Ahead is an open mountain road. "Go ahead," goads the GLS, "have a little fun. No one needs to know." In short order you will find yourself smoothly sashaying this bus down the asphalt at improbable speed. Later, you can convincingly claim none of that happened.
Not-So-Tiny Dancer
In any of its driving modes, under all but the most difficult circumstances, the GLS is surprisingly rewarding to drive. That our first mountain-road experience near Salt Lake City, Utah, was at the wheel of a GLS450 and not the all-singing, all-dancing GLS580 made it all the more surprising. The 450 we drove, like all GLS models, comes with adjustable-height air springs and adaptive dampers but without the trick 48-volt E-Active Body Control (E-ABC) suspension system (more on that momentarily). Still, its body roll is well controlled and progressive, and its steering provided ample feel and precision. Its brakes withstood 50 miles of twisty-road flogging. Back at our Michigan test track, a GLS450 wearing 21-inch Pirelli P Zero PZ4 summer tires stopped from 70 mph in an impressive 154 feet. Pushed to its limit of adhesion on those sticky Pirellis, the GLS orbited the skidpad with a similarly stout 0.92 g of grip.
LOWS: Looks kind of like a Toyota Highlander, expensive, sometimes humps the road.
Okay, the new GLS does look like a bar of soap. But at least the careful manipulation of airflow has reduced wind noise, which helps the GLS's interior remain serene at any speed. That is, apart from the digital assistant for the company's new MBUX infotainment system, who periodically butts in unbidden wondering if she can help with anything. The GLS's ride quality is buttery, not sloppy. Thanks to a more than two-inch increase in wheelbase, the GLS's second-row seats are conspicuously roomy. And for the first time, the GLS is offered with second-row captain's chairs for easier access to the standard third row, which, while tight for tall folks, is considerably roomier than the BMW X7's.
Technology in Motion
The base engine is a hybridized and turbocharged 3.0-liter inline-six that develops 362 horsepower. It's agreeable and refined, if not as smooth as a comparable BMW six. Sending its 369 lb-ft of torque through a nine-speed automatic transmission to the standard all-wheel-drive system, the straight-six is really all the engine you'll need. Our GLS450 test vehicle sprinted to 60 mph in 5.5 seconds and through the quarter-mile in 14.1 seconds at 99 mph. Those are solid numbers for a 5594-pound luxo-barge, matching exactly the performance put in by the lighter BMW X7 xDrive40i. However, the GLS450 is thirstier on the open road than that the X7, delivering 24 mpg in our 75-mph highway fuel-economy test to the BMW's 28 mpg. Still, the big Benz's return on that test is 1 mpg better than its EPA highway estimate.
The uplevel GLS580, however, packs a twin-turbo 4.0-liter V-8 with the same hybridized electric starter/generator as on the six. Mercedes calls this EQ Boost. The V-8's 483 horses and 516 lb-ft is not strictly speaking necessary, but it is smooth and expensive.
You probably don't need the GLS's optional E-ABC setup, either. Ported over from the mid-size GLE-class, this active suspension promises to improve both ride quality and handling by tailoring the springs and dampers individually at each corner. In conjunction with a forward-facing camera, the system can prepare for bumps before they arrive, and it can significantly smooth out off-road terrain. In Curve mode, the system will effectively lean the GLS's body into a turn. The effect is subtler than it might sound, and at $6500, the cost of the E-ABC upgrade is substantial, even within our well-equipped test car's $96,835 final cost. Yet the biggest knock against the option is not its price, but that the standard suspension is so good that it feels superfluous.
Well, it would be except that, with the GLS in the right mode and at a stop, E-ABC can bounce the body up and down in the silliest road-humping routine. It's intended to help free the vehicle from deep sand, which will never happen. But soon you'll see GLS models bouncing at streetlights all over town. Post Malone would totally get that option.
2020 Mercedes-Benz GLS450
front-engine, all-wheel-drive, 6-passenger, 4-door wagon
turbocharged and intercooled DOHC 24-valve 3.0-liter inline-6, 362 hp, 369 lb-ft + AC motor, 21 hp, 184 lb-ft (combined system 362 hp, 369 lb-ft; 0.9-kWh lithium-ion battery)
Suspension (F/R): control arms/multilink
Brakes (F/R): 14.8-in vented, cross-drilled disc/13.6-in vented disc
Tires: Pirelli P Zero PZ4 PNCS, F: 275/45R-21 107Y MO-S R: 315/40R-21 111Y MO-S
Rollout, 1 ft: 0.3 sec
60 mph: 5.5 sec
100 mph: 14.4 sec
¼-mile: 14.1 sec @ 99 mph
Top speed (governor limited): 129 mph
75-mph highway driving: 24 mpg
Highway range: 570 miles