The verdict: It’s pricey, but the posh 2020 Mercedes-Benz GLS-Class makes a solid case to be considered the S-Class of luxury SUVs.
Versus the competition: The BMW X7 matches the GLS for interior luxury appointments, but the Benz beats it with its latest multimedia and suspension tech. American alternatives, meanwhile, have finally caught up in refinement, amenities and glitzy displays.
For many people, the most iconic luxury sedan in the world is the Mercedes-Benz S-Class. Big, smooth and built to impeccable standards, it’s been the world standard for luxury sedans for decades. But the trend toward choosing luxury SUVs over their sedan counterparts has been strong for decades, making the Mercedes-Benz GLS-Class arguably more relevant right now.
For 2020, the GLS gets a major makeover, sharing a platform with the smaller GLE mid-size SUV and receiving a full redo of its interior. It’s certainly priced to be competitive with the S-Class; the base GLS450 with a twin-turbocharged six-cylinder engine is $76,945 including destination fee, and prices can stretch up over $126,000 for a well-equipped GLS580. (And just wait until an AMG version gets here, likely boosting that price even further.) Given these hefty prices, has the redesign of the new GLS truly made it a proper S-Class-level SUV?
Related: 2020 Mercedes-Benz GLE-Class First Drive: Resetting the Luxury Bar
2020 Mercedes-Benz GLS450 | Cars.com photo by Aaron Bragman
Do You Really Need a V-8?
Spacious, smooth and bristling with the latest Mercedes-Benz interior multimedia displays and powertrain and suspension technology, it truly is a luxurious (if somewhat complicated to operate) prestige SUV. The lesser model in the U.S. is the GLS450, which is powered by a mild-hybrid turbocharged 3.0-liter inline-six-cylinder engine making 362 horsepower and 369 pounds-feet of torque. The higher model is the GLS580, powered by a twin-turbocharged mild-hybrid 4.0-liter V-8 engine pumping out 483 hp and 516 pounds-feet of torque. Both engines are mated to a nine-speed automatic transmission and standard 4Matic all-wheel drive.
Both versions are equipped with Mercedes-Benz’s EQ Boost 48-volt mild-hybrid system, though, to be honest, if that system is doing anything at all I’ve yet to figure out what it is. It’s either operating so seamlessly as to be undetectable or it isn’t doing anything and is just a marketing gimmick — either way, it’s a nonissue.
The regular turbocharged I-6 in the GLS 450 is perfectly powerful, torquey, smooth and responsive. It engaged all my demands with flawless action. I had no complaints about its performance during my week with the GLS450, which included several hundred miles of running around the metro Detroit area with multiple passengers and cargo over the December holidays. It has just the right amount of exhaust noise to make you believe there’s something powerful under the hood (engine music that’s piped into the cabin), but it’s quiet and unobtrusive at highway speeds. Acceleration is perfectly adequate in Comfort mode and brisk and entertaining in Sport mode, and it never lets you down when you call upon the powertrain for more. I never ran out of oomph with the I-6 powertrain in the GLS450, regardless of driving conditions.
2020 Mercedes-Benz GLS580 | Cars.com photo by Aaron Bragman
That made me curious about the bigger, more powerful twin-turbo V-8 in the GLS580 I tested the week after I had the 450. The bigger (but not big, compared with some competitors’ engines) V-8 definitely makes itself known when you firmly plant your right foot on the accelerator, launching the SUV with growling authority, but it doesn’t feel any quicker than the GLS450. Even the official 0-60-mph times from Mercedes-Benz don’t show a big difference in acceleration: MB says it’s 5.9 seconds for the 450 and 5.2 seconds for the 580. For 90% of everyday driving you won’t be digging into the deep torque reserves, and when you have a truckload of passengers, neck-snapping acceleration is generally not called for.
You’ll also pay for the privilege of having the V-8 at the gas pump. The GLS450 is EPA-rated 19/23/21 mpg city/highway/combined; my week of driving averaged 19.5 mpg according to the onboard trip computer. The GLS580 is rated worse, at 16/21/18 mpg, and I averaged 15.7 mpg, again according to the computer. I chalk up my subpar fuel economy to the snow tires that both SUVs were equipped with, which likely sapped an mpg or two. So while you’re not doing yourself any favors at the pump by going with the big engine, it’s not like you’re driving a Prius with the lesser engine.
Though neither SUV is super-efficient, they’re on par for the segment: The BMW X7 xDrive40i rings in at 20/25/22 mpg with its six-cylinder engine, slightly better than the base Benz. But the upgraded X7 xDrive50i twin-turbo V-8’s rating of 15/21/17 mpg isn’t as good as the V-8 GLS580’s rating. A Lincoln Navigator, which these days can be mentioned in the same breath as a Mercedes-Benz with genuine credibility, comes in at 16/22/19 mpg for the rear-wheel-drive version and 16/21/18 mpg with all-wheel drive, both equipped with a twin-turbocharged 3.5-liter V-6.
The ride quality of both GLS models is exceptional thanks to a standard electronically adjustable air suspension, plus an optional system called E-Active Body Control. That system uses a combination of sensors, cameras and actuators to anticipate the vehicle’s next move and adjust the body accordingly. For instance, if you’re turning into a banked curve on a highway or twisty road, forward-scanning cameras watch what’s coming and the system can tilt the GLS’ body like a motorcycle or airplane banking into the corner. It dramatically reduces the centrifugal force you would normally feel throwing you against the doors when you take a tight corner, reducing passenger fatigue and giving a better sense of control over the SUV in general. It truly is a must-have option on any Mercedes-Benz SUV that offers it; it’s a unique system not found on any competitor.
2020 Mercedes-Benz GLS450 | Cars.com photo by Aaron Bragman
The cabin of the new GLS-Class is fully updated to the modern Mercedes-Benz standard, and it’s a welcome change. The old cabin was getting long in the tooth, using the brand’s old-style switches and buttons, but the new ones look as fresh as anything in the lineup. Slim stalks on the steering column, excellent aluminized finish on the dashboard buttons, classy-looking genuine wood trim and luxurious-feeling high-grade leather are all in abundance. And unlike the latest Audi designs, it’s not all touch-sensitive flat plastic panels. Mercedes-Benz apparently believes (correctly, in my opinion) that you still need the feel of a switch or button to properly convey a sense of precision, price and “premiumness.”
The highlight of all the new Benz interiors is the dual electronic display screen that stretches across the dash, from the driver’s gauge cluster to the right side of the center console. In the GLS, it’s sized as two 12.3-inch screens, the right-hand one being touch-sensitive. The driver’s display can also be switched between a few different themes, and there’s a full-color, reconfigurable head-up display available so you don’t have to take your eyes off the road for critical information.
The MBUX multimedia system is standard, and it works as it does in other Mercedes-Benz vehicles — mostly good results, despite a few nagging glitches inherent in its design. There are two problem areas with the system: First is the voice recognition that’s meant to activate the Siri/Alexa-like assistant whenever you say “Hey Mercedes,” but that actually activates anytime you just say “Mercedes,” making talking about the vehicle while driving it challenging. The other trouble area is the steering wheel, which has the latest touch-sensitive five-way controllers on the spokes, meaning you have to be very careful not to touch them lest you accidentally change a setting or activate a feature. Having an area on the steering wheel that you have to consciously avoid touching while driving is lunacy, and the system is not an improvement over the old five-way controllers Mercedes-Benz used to employ.
In the end, though, you can forgive all that thanks to the comfort provided by the larger, more spacious interior versus the one it replaces. The new model has a 2.3-inch stretch to its wheelbase, which has translated into more than 3 extra inches of rear legroom thanks to a newly adjustable second row. It’s still tight in that third row for full-size humans, but it’s less of a chore to sit back there given the ability to negotiate legroom among backseat passengers. The first row of seats is multi-adjustable, as well, and outward visibility is excellent thanks to a commanding driving position and big, tall windows.
Cargo room is also plentiful, measuring 17.4 cubic feet behind the third row, 42.7 cubic feet behind the second row (or 48.7 cubic feet with the second row scooched all the way forward) and a maximum of 84.7 cubic feet with all the rear seats down. The BMW X7 has comparable overall volume but only 12.8 cubic feet behind the third row. There’s 48.6 cubic feet behind the second (not adjustable) row and a maximum volume of 90.4 cubic feet when all seats are folded. If cargo room is really your priority, however, you’ll want to look at a Lincoln Navigator, which boasts 20.9 cubic feet behind the third row, 57.5 behind the second and 103.4 overall. And that’s just the regular-length version; the Navigator L sees those numbers climb to a cavernous 36.0/79.6/120.3 cubic feet.
Aside from the engine, what else differs between the GLS450 and GLS580 that could justify a $22,000 difference in base prices? Honestly, not much. There’s some additional standard equipment on the GLS580, such as heated and ventilated multicontour massaging front seats (you have to pay extra to get the ventilation and massage on the GLS450). The 580 gets five-zone automatic climate control (the 450 can have four-zone), illuminated running boards and soft-close doors standard. Visually, the two differ only slightly: standard wheels on the GLS450 are 19 inches, while the 580 gets 21-inchers. There are also some option packages you can get only on the 580, such as a Night Package that brings blacked-out trim, and an AMG Line Package. Both give the GLS different trim, bumpers, grilles, etc. You can go up to 21-inch wheels on the 450, but the 580 lets you specify some massive 23-inch wheels and tires as options.
The base GLS450 comes so well-equipped that aside from the bigger, more powerful engine and a little bit of extra equipment, there isn’t much to justify the additional cost to upgrade to a GLS580. It seems the main reason to go for the more expensive version is simply the prestige of having the bigger number on the tailgate. Until the new ultra-lux 2021 Mercedes-Maybach GLS arrives sometime this year, the 580 will occupy the top spot in the lineup. But unless you absolutely must have that number on your tailgate, save yourself a pile of cash and go for the just-as-good GLS450, then option it up with a lot of the stuff you’d have to pay for on the 580 anyway, like the Executive Rear Seat Package, the E-Active Body Control suspension (an absolute must) and the Driver Assistance Package.
The GLS has a more versatile interior than a BMW X7 and much more technology than a Lincoln Navigator. (Compare the GLS to its competitors here.) The new 2021 Cadillac Escalade is out but we haven’t driven it yet; its new digital dash and fine leather interior may give the GLS a run for its money, and its size rivals the Navigator. But until we get some time behind the wheel of that monster, the GLS remains our pick for the best three-row luxury SUV for the money.
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