Test Drive: 2017 Mercedes-Benz GLS 450

In the realm of full-size luxury SUVs, the Mercedes-Benz GL-Class has always stood apart. Introduced for 2002 and with the second generation debuting for the 2013 model year, the GL – which has been given a mid-cycle refresh and renamed GLS for 2017 – is the sole German entry in the segment. Audi's Q7 is probably the nearest European rival, but it's officially classed as a mid-size vehicle and doesn't offer the third-row comfort of the big Benz. BMW's X5 and Porsche's Cayenne? Not even close.

Overall the changes are quite subtle, but then why mess with success?

No, if you want a competing luxury SUV that offers space on par with its opulence, you need to look to the Japanese (Infiniti QX80 and Lexus LX570), the Americans (Cadillac Escalade and Lincoln Navigator), or the British (Land Rover Range Rover).

The name change from GL to GLS reflects a simplification of Mercedes-Benz's SUV naming convention, which now echo the company's car-naming convention except with "GL" added on. So, the GLK becomes the GLC (being the SUV equivalent to the C-Class sedan), the ML-Class becomes the GLE (being equivalent to the E-Class) and the GL becomes the GLS (being equivalent to the range-topping S-Class sedan). Don't mind the G-Class, which is imposing enough that it doesn't need any extra letters.

The GLS's refresh for 2017 encompasses a number of changes including styling updates, an updated interior, a new transmission, retuned ride dynamics, and new tech features.

The exterior styling updates include a good-looking new grille, new front fascia, new LED headlights, and revised taillights. Inside, there's a redesigned dashboard, a handsome new three-spoke steering wheel, a bigger infotainment screen, and a new infotainment touchpad controller. Overall the changes are quite subtle, but then why mess with success?

The new 9G-Tronic transmission, as the name implies, now has nine speeds instead of seven, with shorter ratios in the first seven gears (giving improved responsiveness) and taller ratios in the top two gears (giving improved highway efficiency). On the road, I found it to be well-matched to the GLS 450's 3.0L V6 bi-turbo gasoline-powered engine. In manual shift mode, the transmission features rev-matched downshifts and lightning-quick shift responses that put some so-called sports sedans to shame, and on the highway it's geared such that the engine turns only 1,300 rpm at 100 km/h. Final drive is via Mercedes-Benz's 4Matic permanent all-wheel drive system, which I wasn't able to test in the sunny, dry conditions prevalent when I had GLS 450, but which has enough electronic wizardry to give the big rig reassuring surefootedness in slippery winter conditions (just as one example of the GLS 450's electronic wizardry, there's a standard-fitted crosswind assist system that discreetly corrects the vehicle's steering line when a strong gust of wind is encountered).

See also: 2017 Mercedes-Benz GLS-Class First Drive

The engine in the GLS 450 is the smallest gas engine in the GLS lineup; however, it still packs plenty of punch, churning out 362 hp at 5,250 rpm and 369 lb-ft of torque way down low at 1,800 rpm – good enough to propel the 2,420 kg (5,335 lb) SUV from 0–100 km/h in a respectably quick 6.6 seconds, with a muted but satisfying bellow at wide-open throttle. If that's not really fast enough for you there's always the 449 hp V8-powered GLS 550 (0–100 km/h in 5.6 seconds) or the entirely bonkers 577 hp Mercedes-AMG GLS 63 (0–100 km/h in a mere 4.6 seconds, which should be plenty quick enough to wake the kids up with a fright). Those who prefer a more fuel-efficient diesel-powered ride will have to sit under the wait-a-bit tree for a while, however, as the revised (and slightly more powerful) 3.0L diesel hasn't yet cleared the EPA's stringent post-Dieselgate scrutiny.

Happily, given that you can't get the diesel yet, the gas-powered 2017 GLS 450 is a good bit more fuel-efficient than the previous model: Where the 2016 GL 450 was rated 15.2 / 12.6 L/100 km (city/highway) Mercedes-Benz's documentation has the new rig coming in at 14.4 / 11.4 L/100 km. In terms of actual fuel consumption, my test vehicle was showing a long-term average of 16.8 L/100 km when I picked it up, and the best I saw was 12.4 L/100 km on a 40 km mixed highway/suburban run – not bad for a vehicle that can haul seven people in comfort and tow 3,500 kg (7,716 lb). Adding a bit of extra expense at the pump is the fact that the turbocharged V6 requires premium fuel.

Heading up the retuned ride dynamics for 2017 is a new Dynamic Select controller that allows you to adjust the powertrain and suspension settings to suit your driving style and road conditions. The default Comfort setting provides the calm, unflappable (if slightly ponderous) ride and smoothly powerful acceleration you'd expect from a big Mercedes-Benz. Flip into Sport mode and the suspension firms up, the throttle response becomes more eager and the transmission mapping more aggressive (you might almost say perhaps a little too aggressive). It's a pretty striking Jekyll-and-Hyde transformation, and the GLS 450 is impressively taut and responsive feeling for such a large vehicle when in Sport mode – indeed, it becomes downright fun, if a bit of a guilty pleasure. Additional modes include a snow mode, a rough-terrain mode, and an Individual mode, which was my favourite as it allowed me to firm up the ride without engaging the overeager Sport throttle and transmission mapping. Regardless of the mode selected, the GLS remains exceptionally solid feeling, and wind noise is well-damped (although I did notice a little bit of tire hum from the big 21-inch Continental Cross Contacts).

Inside, the 2017 GLS 450 is properly comfortable and accommodating, with roomy and supportive front seats, plenty of space in the second row, and room for real-size adults in the third row provided the second-row seats aren't reclined all the way back. Cargo space is 453 L behind the third-row seats (295 L under the cargo cover), 1,399 L behind the second-row seats, and 2,656 L with all seats folded.

Interior materials include a stitched leather-look dash topper, soft-touch front and rear door uppers, soft-skinned console sides and cloth-wrapped roof pillars, and my test car raised things up a notch further with gorgeous-looking optional ($250) open-pore ash wood trim. Parts like the door lowers and cargo liner are rigid plastic, as expected, but perhaps less expected in this segment is that the standard seat upholstery is man-made Artico ("artificial cow") leatherette. Real leather is available, of course (it's a $1,990 option), although the Artico leatherette looks convincing enough that I thought it was genuine leather for the first couple of days.

The new touchpad controller is cantilevered above the traditional rotary control knob, and it recognizes smartphone pinch and swipe gestures. Truth be told, my peanut-sized brain found the splitting of input duties between the touchpad and the rotary controller to be a little confusing and awkward, but I'm sure with time it would become second nature (heck, even I eventually adapted to the combined use of a mouse and keyboard, so why not?)

Standard conveniences include things like dual-zone automatic climate control, 360-degree rearview camera, power-operated heated front seats with memory, power-folding third-row seats, satellite radio, Bluetooth wireless audio streaming, Apple CarPlay, navigation, Mercedes-Benz COMAND online apps, and much more. Indeed I could go on listing the standard features for quite some time, but suffice to say it's enough to create an interior environment that's very nearly perfect (but not quite perfect – I found the A-pillars to be rather obstructive, I still don't like the Mercedes-Benz twist-to-operate wiper control, there aren't enough USB outlets, and the infotainment interface, while reasonably intuitive, is rather complicated, requiring six steps to change the seat massage settings, for example).

Then there's the available packages, which allow you to load up your GLS with enough equipment to make it truly worthy of an S-Class sedan, both in terms of luxury and safety. My test vehicle was fitted with many of these. First up was the Premium package, which includes multicontour front seats with massage, soft-close doors, heated rear seats, climate-controlled cupholders, panoramic sunroof, "Easy Entry" power tilt for the second-row seats (you have to redeploy them manually, however, and it takes a bit of grunt), fantastic-sounding Harman Kardon Logic7 surround sound system, roller blinds for rear side windows, and power pop-out third-row windows.

Next up was the Intelligent Drive Package, which adds on a regular alphabet soup of active safety systems including Distronic Plus with steering assist (I've no idea what it stands for, but it incorporates active cruise control), active blind spot assist, active lane keeping assist, Pre-Safe Plus for rear-end collision (I'll hazard a guess that this helps prevent rather than cause said collisions), BAS Plus with cross-traffic assist (the BAS stands for Braking Assist System), Pre-Safe Brake autonomous emergency braking and something called CMS Rear (I think this means "cross-traffic monitoring system rear").

Finally there was the Sport Package with Adaptive Damping System Plus, the Night Package appearance package (blackout mirrors, blackout trim, and unique AMG wheels), and an Air Balance package, which allows the interior of the vehicle to be scented with your choice of four different fragrances. I kid you not.

Pricing for all this comfort, luxury, and technology starts at $82,900, which puts the Mercedes-Benz GLS 450 on solid footing against rivals like the Cadillac Escalade (starting at $84,145), Lexus LX 570 (starting at $105,000) and Infiniti QX80 (starting at $74,650). Where the Mercedes-Benz GLS 450 stands out is in its conservative good looks, exceptionally refined driving experience, accommodating third-row seating, and comprehensive array of available driving assist features. If a big luxury SUV is on your shopping list, it's a must-see benchmark contender.

Warranty:
4 years/80,000 km; 4 years/80,000 km powertrain; 5 years/unlimited distance corrosion perforation; 4 years/unlimited distance roadside assistance
2017 Mercedes-Benz GLS 450
2017 Mercedes-Benz GLS 450
Base Price $82,900
A/C Tax $100
Destination Fee $2,495
Price as Tested $97,295
Optional Equipment $11,800 (Premium Package $4,900, Sport Package $3,200, Intelligent Drive Package $2,700, Night Package $500, Air Balance Package $250, Open-pore Ash Wood Trim $250)
Optional Equipment
10 0
Scoring breakdowns 8.4
9 Interior
7 Fuel Economy
9 Exterior Styling
8 Performance
9 Comfort