The premium people-carrier battle begins in earnest from 2020, with a new-generation Mercedes-Benz GLS fresh on Aussie soil and ready to bare its teeth to the BMW X7.
Of course, seven-seat SUVs from prestige brands are nothing new. The Audi Q7 and seven-seat versions of the smaller Benz GLE and BMW X5 have long offered the flexibility of ‘+2’ third-row seats, but the new flagships are grand SUVs done properly.
In the case of the 2020 Mercedes-Benz GLS, Australians will have a choice of two mainstream models initially: the petrol-powered six-cylinder GLS450 and the more popular six-cylinder diesel GLS400d driven here.
The range kicks off with the GLS450 starting at $144,600 before on-road costs, while the GLS400d asks for $151,300. Apart from their engines, both will share the same key specifications, but should you be looking for more, bellowing AMG GLS63 S and ultra-plush Maybach GLS600 versions are slated to arrive in the third quarter of 2020.
The more mainstream GLS400d kicks things off with Mercedes’s new-generation inline six-cylinder diesel engine. Benz officially calls it a 3.0-litre, though specifications reveal it to be a 2.9 (if you’re splitting hairs that finely) good for 243kW and 700Nm.
Lined up against the outgoing GLS350d of the previous generation, the new engine provides a handy 53kW and 80Nm of extra grunt, hence the badge size markup. Fuel consumption is rated at 7.7 litres per 100km officially. Purely urban driving snuck into the mid-nines, and a day of mixed driving clocked a very decent 8.3L/100km, given the size and weight of the new GLS.
For owners stepping out of the older car, you’ll find overall length is now 77mm longer (5207mm in total), width grows by 22mm (1956mm), there’s an extra 60mm between the front and rear wheels (3135mm), but overall height drops slightly by 27mm (1823mm). If you’re keeping track, kerb weight is a hefty 2490kg.
The increased dimensions are designed to enhance interior space, with the second-row seating claimed to be suitable for passengers up to 200cm, and the third row recommended for use by passengers up to 194cm.
Without a basketball team on hand to fully investigate, we had to resort to a 186cm passenger who easily fitted the second row, but still found the third row snug without being constricting. While there was plenty of head room, outward visibility was limited thanks to the tall seatbacks in front.
Further back, luggage capacity is 355L (+20L over the preceding generation) with all three rows of seats in place or 890L (+210L) with the third row folded, and 1470L with all rear seats stowed away. Loaded to the roof, those capacity figures are 470, 1350 and 2400 litres respectively. Under the boot floor there’s a dedicated stowage space for the cargo blind, and regardless of the wheels fitted (from 21-inch to 23-inch) a space-saver space comes standard.
Given the GLS is designed as the SUV range’s family flagship (the more hardcore G-Class sits on a pedestal of its own), you’d expect that the GLS, like the S-Class sedan, would be kitted out with full glitz and glamour inclusions.
Certainly, Benz has some impressive tech highlights at its disposal, and attention-grabbing equipment like dual 12.3-inch widescreen infotainment and instrument displays tied to the latest MBUX infotainment system with touchscreen, steering wheel touchpad, console touchpad, and ‘Hi Mercedes’ conversational voice inputs to control just about every function found within the car – from navigation to seats to lighting to mindfulness coaching (yes, really!).
Once you find your own comfortable way to use the system it's pretty intuitive. The car can tell if a driver or passenger is speaking to it, or reaching for the screen, and make adjustments accordingly. There are some gimmicky touches like 'augmented navigation', which uses the front camera feed to give a live map overlaid with directions. Some in the CarAdvice office love it, but I didn't find it very useful.
Some things, like seat massage settings or third-row climate controls, seem a little too deeply buried, but practice makes perfect. The giant head-up display can be confronting at first, but offers 'at a glance' recognition. The main instruments are configurable, so displays are yours to dictate.
Standard inclusions for Australia see all models equipped with AMG Line exterior styling, 21-inch five-twin-spoke AMG alloy wheels, leather upholstery, power-adjustable multi-contour front seats with heating and ventilation, 13-speaker Burmester sound system, head-up display, and five-zone climate control.
The goodies don’t stop there, though: a sliding panoramic sunroof, powered tailgate, soft-close doors, adaptive cruise control and speed limiter, active park assist, air suspension, 360-degree camera, lane-keep and lane-change assist, blind-spot assist, and rear cross-traffic alert.
The features list is every bit as plump as you’d expect, but in terms of presentation, Mercedes-Benz doesn’t quite configure the new GLS with the look and feel some buyers might expect.
Though it’ll no doubt be hard-wearing, the firm, coarse-grained leather trim doesn’t feel plush or luxurious, and in places looks mismatched alongside the fake leather ‘Artico’ dash and doors. Some of the switchgear (like the suspension height toggle) lacks solidity and heft, while the column-mounted gear selector has a distinctly flimsy action.
If you’re loading kids into the third row they may not notice, but under the row-two seats Mercedes has left a jumble of exposed wires and seat motors visible when the seats are flipped forward. Return the power-sliding second row into position and it defaults to a bolt-upright position, requiring adjustment every time – all of which is a little disappointing.
At least power operation means each seat can be folded from within the boot, and pressing the ‘all’ button whisks rows two and three flat into the floor quickly, unlike the achingly slow BMW X7, for instance.
On the plus side, there are six USB-C power outlets in the rear of the cabin, plus three more up front. Middle-row passengers get left and right climate zones and air vents in the roof, B-pillars and console. Rear passengers get roof vents, but need to ask front seat occupants to alter temp and fan speed with no rear controls included.
At least there’s a microphone pick-up within the cabin to negate the need to shout back and forth.
For the driver, the GLS400d impresses with its massive wall of torque available at just about any point in the rev range, though given the GLS’s relaxed demeanour there’s no need to rev at all, letting the prodigious mid-range do the heavy lifting.
Acceleration to 100km/h is a claimed 6.3 seconds in the diesel (or 6.2 seconds in the petrol GLS450), which seems utterly incredible for something of this size and weight. It’s certainly brisk after a dull moment just off idle before swinging into force.
All-wheel drive is standard, and Mercedes’s well known nine-speed automatic provides the link between engine and wheels. It’s a transmission that offers no surprises: smooth and calm, though at times reluctant to kick down should you need a shot of overtaking acceleration.
Road and wind noise are excellent. If you work the engine, you can hear it protest. Some may like its gravelly tone, but others could find it unbecoming of a $150K luxury conveyance.
Similarly, the standard air suspension doesn’t have the polish you’d expect of something positioned the way the GLS is. Around town, the air springs struggle to damp out little bumps and dips, with the car jiggling over small imperfections or seesawing its way across bigger dips.
There’s no missing the size of the thing on the road. Its length creates challenges in carparks, and inner-urban dwellers will need to carefully choose their journey based on streets with enough clearance.
For all of that, though, the steering is light enough to feel nimble, but dulled off so as not to upset the balance. Mercedes’s driver assist allows for highway cruising, with adaptive cruise control and lane keeping that feel natural and take some of the load off the driver.
As generously equipped family transport, the GLS fits the bill perfectly. Seating is spacious, and there are more than enough amenities to keep driver and passengers entertained, safe and comfortable.
Where Benz drops the bundle is the final veneer of quality and presentation. This isn’t the S-Class of SUVs – a smattering of creaky interior plastics, jittery suspension, unappealing leather trims and exposed seat wiring do not invoke Mercedes’s ‘best or nothing’ mantra.
Buy the GLS400d for the badge if you must – or the space and utility on offer, absolutely. Don’t turn to this one seeking ‘the best’, however. There are no major failings in the final product, but Mercedes-Benz seems to have overlooked some unfinished edges.