Mercedes-AMG GLS63 2021 63 4matic (hybrid)

2021 Mercedes-AMG GLS63 review

Rating: 8.4
$267,100 Mrlp
  • Fuel Economy
  • Engine Power
  • CO2 Emissions
  • ANCAP Rating
How's the German hot-rod treatment go on a big, seven-seat family bus?
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The whopper. The big kahuna. Big cheese. Or maybe Grand Poobah? These are all phrases that I kept dishing out whenever someone enquired about the rather meaty 2021 Mercedes-AMG GLS63.

That's because it is all of those things – some good, some bad. As the top dog (there's another) of Mercedes-AMG SUVs, it needs to deliver.

We'll kick off with where the GLS63 sits in the wider AMG SUV range. It's priced from $255,700 before on-roads. That's precisely $33,000 more than the five-seat GLE63 Coupe with 'coupe' body type, or $35,100 more than one with a conventional SUV body.

Given the space and prestige upgrade you receive against the overall cost outlay, it's fairly priced.

Our car was also relatively devoid of options, surprisingly. At this level it's not irregular to see $50,000-plus worth of extra gear. It had $10,900 worth added, which includes unnecessary 23-inch forged-aluminium wheels ($3900), the necessary carbon interior package ($4200), and circumstance-pending rear-seat comfort package ($2800).

Total damage for the big shot? $266,600 before on-roads, or about $280,000 drive-away.

2021 Mercedes-AMG GLS63
Engine configuration4.0-litre twin-turbo petrol V8
Displacement4.0 litres (3982cc)
Power450kW at 5750rpm (+16kW EQ-Boost)
Torque850Nm at 2250-5000rpm (+250Nm EQ-Boost)
TransmissionNine-speed automatic AMG Speedshift TCT
Drive typeAll-wheel drive
Tare weight2710kg
Fuel claim, combined13L/100km
Fuel use on test17/100km
Turning circle13.1m
ANCAP safety rating (year tested)Not tested
Warranty (years / km)5 years / unlimited km
Main competitorsBMW X7, Range Rover Vogue
Price as tested$266,600

Naturally, driveline figures are huge. The 'M177' 4.0-litre twin-turbo V8 engine in this trim produces 450kW and a massive 850Nm between 2250–5000rpm. But that's not all, as the GLS63 is equipped with a clever 48-volt electrical architecture, as per most modern and large European performance vehicles.

A clever alternator not only saps from the engine, but also gives back – providing 16kW and 250Nm to the mix. Dizzying figures in total, but slightly numbed due to a 2.7-tonne tare weight.

The performance is muscular considering its size and mass, but scarily it doesn't convey the speed it puts on. It's one of those cases where you nail the throttle, feel less g-forces than expected, then look at the speedo and go "yeah, right".

Other AMGs in the range, from the mighty A45 S right through to the utterly brutal GT R sports car, all relay the vital essence of acceleration and performance back to you as the driver. They all communicate speed rather well. So well, in fact, that it's become an expectation after getting into a vehicle adorned with those magical capitalised letters on the back.

Still, it's fast according to the speedometer, even if it sadly doesn't feel it. Going from 60km/h to 110km/h via a motorway on-ramp is completed almost instantly. Actually, that's more the case with all roll-on acceleration events.

The engine's clever design mitigates long pipes for its turbochargers to expel through, which reduces lag. Add in the alternator starter's aid, and the resulting net effect is super responsiveness. You'll just have to keep the windows down, though, or monitor others fading into the distance in order to notice its pace.

There's an adaptable sports exhaust fitted as standard, which lifts the decibels significantly. In regular mode it lets out a subdued V8 hum, and when fully open creates the signature soundscape of being followed by rolling thunder. Not as raucous as old, naturally aspirated AMG V8s, but still of similar quality. Hits and misses, remember?

Fuel use came in at 17.0L/100km. The official claim is 13.0L/100km. If you're going to be motoring in and around metro environments, it'll be achingly thirsty. Out on the motorway, however, efficiency does improve to the 11–12L/100km mark.

A heavyweight, both literally and figuratively, which is surprising considering how it moves. Like the motor, the chassis is brimming with tech. Alongside air suspension, there's a smart active roll stabilisation system.

I like to go into cars blind, then read about the fancy things afterward to see whether they're gospel or thesis. I had noticed that flicking between Comfort mode and either Sport or Sport+ modes in a straight line, on choppy terrain, didn't introduce stacks of extra firmness. Sure, road lines and prominent markings become more obvious, but the experience didn't morph aggressively. However, as soon as you steered, the difference became stark.

In the most comfortable setting, roundabouts taken swiftly were taxed by mass and roll, which seemingly reduced the grip reserve. In the sportier modes, the vehicle felt like it both dropped a few hundred kegs and somehow added strengthening braces underneath.

It laughed off the feeble gauntlet I laid down earlier. What's great about the technology is that it works when it needs to and doesn't interfere when asked not to.

On top of that point, it's incredible what it adds to the GLS63's repertoire. Out through flowing country lanes, where the speeds are high and the roads beautiful, it felt all the part AMG, and in turn dignified.

Ride quality in Sport is involving but not intrusive. More importantly for a car weighing 2.7 tonnes, however, it'll tackle switchbacks with ease.

Around town, its air suspension is plush as. Comfort mode in fact turns it into a huge rolling pin, which transforms mottled roads into billiard tables. I often caught my three-year-old napping more than usual, partly due to the wonderful ambiance the big enchilada puts on for its guests.

Which starts at the front. Taking centre stage is a pair of 12.3-inch screens, with one handling infotainment and the other driver information. This 'MBUX' system is wildly complex, with a massive array of configurations and ability.

As I've said before, sit down with a bottle or glass of your favourite beverage one evening and read the bloody manual – front to back, then maybe back to front for good measure. You'll not only learn the sneaky shortcuts that reduce distraction behind the wheel, but you'll learn how to harness its power for your own convenience.

In terms of quality, the screens are fantastically sharp and clear. They're also powered by processors and graphics units with enough mumbo to make complex animations appear fluid.

Something else that's great is the operating concept Mercedes-Benz has applied. There are multiple switches everywhere for the same thing. For example, you can either turn on the exhaust via a toggle switch, the steering wheel or the drive-mode selector. The same goes for forcing the transmission into manual-only mode, as well as a host of other items.

You can also interact with the car's centre screen three ways: through a small touch-sensitive button on the steering wheel; a large touchpad with haptic feedback; or by touching the screen itself with your finger – plus the always there fourth option of voice commands.

It may seem counterintuitive to have the same features operated myriad ways, but it actually changes how we interact with the car. It also continually reminds you about what's on offer. It provides dedicated shortcuts to things that you love and may have forgotten about, and allows you to operate them in a way that you prefer.

Some like buttons, some like touchscreens, others save their preferences into one overarching drive mode. Everyone has cake, which they can eat.

In terms of more basic and practical elements, it feels absolutely huge inside, as it ought to. Two huge door pockets allow for bags, water bottles and the like. There are some nifty tricks like heated and cooled front cupholders, plus a well-sized armrest area with heated lid – to warm your elbows.

The tall glasshouse creates decent visibility, but given its size and cosseting nature, it can be hard to gauge the big whopper's extremities in tighter parking situations.

As this is a Merc with 'S' in its designation, it features every possible form of active safety system. It'll try its best to stop if you approach a pedestrian or car unknowingly, hold its position in a lane, adapt cruise control, read traffic signs, and assist evasive steering efforts, to say the least.

As for an official ANCAP safety rating, the GLS63 remains untested in the Australian market.

Moving on to the second row, most of its dimensions are generous. The only one that isn't is knee room, as I found there to be around 3cm of space behind my driving position. I was expecting more.

All other dimensions are above and beyond what they need to be. Door-mounted seat controls allow occupants in either outbound seat to adjust their seat forward or backward, recline the seat back itself, lift the headrest, and even heat their tushes.

Loading kids in and out is as easy as it comes with a vehicle this size and height, regardless of whether the seat is forward-facing, rearward-facing or a removable capsule.

It's possible to install three child seats across the second row if you don't opt for the rear-seat comfort package, as per our test vehicle. That option package also adds more gizmos, one of which is an integrated rear tablet. Located in the fold-down armrest, it gives second-row occupants complete control of their immediate surroundings, and even acts as a mousepad for the screen up front.

I'd suggest not showing your kids that feature, unless you want them to muck about with your settings unbeknownst to you as you drive. With the choice, you also receive an extra wireless charging pad in the same armrest, luxury headrests, and a third heated and cooled cupholder.

Second-row air vents are everywhere. You'll see them in the back of the centre console above two USB-C ports and climate-control buttons, in the side pillars, as well as in the roof. It's possibly the most comprehensive second-row cooling effort I've seen. It's also possibly the grooviest second row out there, with heaps of LED 'ambient' lighting strips that create more of a disco vibe.

Finally, the third row. Accessing the last two seats is made possible by a completely electronic system that lifts the seat up and concertina folds it forward. Despite the big show, well, putting on a show, it doesn't leave that big of a gap to climb through. It also takes quite a while to complete.

Once seated, however, it's a nice place to be, adult or child. Guests have a huge window to peer out from and be bathed in light – something essential to general habitability.

As for physical space, adjustments must be made to fit an adult back here. To not bash knees up against the hard, second-row seat back, the middle seating must be adjusted slightly more forward.

Thankfully, when you use the electronic system to access the third row, it smartly lowers the second row back into a position conducive to third-row occupancy, regardless of where it started. That means second-row occupants lose 3-4cm of leg room when the GLS is in seven-seat mode. Ideally, teenagers and below will remain in the utmost comfort across all five rear seats.

Adults will lose some space, but not enough to cause discomfort. In case you want to run two child seats in the back, the third row is also equipped with ISOFIX points. This opens up a variety of seating options, including leaving the second row free for those who would find clambering into the third row hard.

There's also a cupholder each side in the third row, as well as four USB ports for only two people.

Behind all the action lies a mammoth boot. In seven-seat mode there's 355L (more than a Toyota Corolla or Mazda 3 hatch), in five-seat mode a fantastic 890L, and with both rows of seating folded, a staggering 2400L. If you want a family car that doubles as a part-time van, here you are.

Folding the seats is conducted electronically via switches in the cargo area, which both drop and lift the seats at will. There's also a button to drop the vehicle's suspension down for the easier loading of heavy cargo, or fido, which may be considered the same thing.

Under the boot floor is a low-speed spare wheel, as well as storage for the cargo blind.

You'll never be short of space in a GLS63, nor late either. It's a huge car with equally huge performance – so long as you take the time to notice.

The only other concern is how large it can feel at times. Newcomers driving vehicles of such dimensions will find it challenging, but seat time will likely alleviate or normalise the sensation for most.

I'll hastily assume the fuel bill won't bother you either. A lavish choice, if you can afford it.

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