Mercedes-Benz GLS 2020 450 4matic (hybrid)

2020 Mercedes-Benz GLS450 long-term review: Touring

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A big car needs a big country, and James finally has the chance to stretch the GLS's legs.
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Finally a chance to hit the open road!

Like many around the country, my family and I were confined to our immediate home area for the majority of last year, so with school holidays, relaxed restrictions and the 2020 Mercedes-Benz GLS450 all in alignment, we got out of town.

The GLS has been in our care since August, so you can catch up on the introduction and urban-living updates here.

In a ‘too-long, didn’t-read’ mood? Here are the Cliff’s notes…

The Mercedes-Benz GLS range starts at $147,100 (before options and on-road costs) for the 3.0-litre turbocharged six-cylinder petrol GLS450, like ours. You climb to $153,900 (an extra $6800) for the 2.9-litre six-cylinder turbo-diesel GLS400d, or add a massive $108,600 to get to the monstrous, $255,700 4.0-litre twin-turbo V8 petrol GLS63.

In all engine configurations, the GLS is seven-seat, luxurious techno-sandwich that is a substantial 5.2m long and 2m wide, and has a cavernous 2400-litres of cargo space.

Our Selenite Grey ‘450 includes $18,400 worth of options, which is heavily underscored by the $13,000 E-Active Body Control (EABC) system, but more on that shortly.

2020 Mercedes-Benz GLS450
Engine configurationInline six-cylinder turbocharged petrol (with 48V mild-hybrid)
Displacement3.0L (2999cc)
Power270kW @ 5500rpm (+16kW EQ-Boost)
Torque500Nm @ 1500–4500rpm (+270Nm EQ-Boost)
Transmission9-speed (9G-Tronic) automatic
Drive typeAll-wheel drive
Weight (Tare)2656kg
Power-to-weight ratio101.7kW/t
0–100km/h claim5.2sec
Fuel consumption (combined cycle claim)9.2L/100km
Fuel consumption (combined cycle on test)9.1L/100km (touring)
Fuel tank size90L
Turning circle12.01m
Sales categoryUpper-Large SUV (premium)
Key competitorsBMW X7 / Audi Q7 / Land Rover Discovery

Now, I’ll level with you.

I had intentions of getting to the four points of our state over the two-week holiday break, but with everything else that has to be organised, these dreams were scaled back somewhat.

That said, I can say that the GLS is a brilliant tourer.

Just after Christmas, we headed west to visit some friends in Creswick, in the heart of the Victorian goldfields.

With the third-row stowed, I filled the 890-litre boot with luggage and had plenty of room to spare. The huge amount of legroom and reclining seats in the back provided ample comfort for Miss-11, although, who would know as she stayed buried in her phone the entire trip…

Car set to comfort mode, and seat massage on, we began the 127km journey!

2020 Mercedes-Benz GLS450
Ground clearance199mm (adjustable)
Boot volume355L / 890L / 1470L (2040L to roof)
Tow rating (unbraked / braked)750kg / 3500kg
Wheels/tyres22-inch – 285/45R22 front, 325/40R22 rear Continental

Mercedes has always lead the way with cruise control and driver assistance technology, and the suite in the GLS is no exception.

You can display an image of how far the car in front of you is on the head-up display. This makes it easy to time your overtaking without having the distance braking cut in, which is a regular source of frustration with many adaptive cruise implementations.

On a well-marked freeway, the lane-keeping aid is mostly imperceptible, allowing you to balance the car with a light touch for a relaxed drive.

The ride comfort is excellent, as the EABC system constantly adjusts the air suspension dampening rates to better absorb bumps. Fair to note, that a freeway is mostly smooth, and as such isn’t a great testbed for some of the car’s ride and handling capabilities, but dropping onto some more winding B and C-roads changes things up somewhat.

Where the comfort program enables the car to soak up bumps and imperfections, changing to the Curve drive mode activates the dynamic corner levelling ability of the GLS.

Here, when you tip into a bend the raises on the outside, where it would normally compress. Like a high-speed train that leans into a corner, this counteracts the centrifugal force exhibited on the occupants and makes the car feel level.

It’s a bit surreal and acts in a way that substantially lessens the impact of the corner. The upside is ride comfort, but the downside is you are almost goaded into taking bends much faster than the advisory sign, as you simply don’t feel the car moving as much.

Whichever way you look at it though, and despite the price of the option, it’s very clever and hugely impressive.

Most impressive though is the fuel consumption.

2020 Mercedes-Benz GLS450
ColourSelenite Grey Metallic
Price (MSRP)$147,100
Options as tested$18,400
Servicing 3yr$2700
Servicing 5yr$5200
ANCAP safety ratingNot yet tested
Warranty5 years / unlimited km

Heading to, and then from Creswick, I was able to average 9.1L/100km on both trips, door-to-door. This is above the highway consumption claim of 7.9L/100km, but is bang on the 9.2L/100km combined cycle claimed by Mercedes.

This is a 2.7-tonne beast, with fuel, family and cargo aboard, travelling at 110km/h on an undulating highway. What’s more, if you opt for the diesel, the combined consumption comes down to just 7.7L/100km.

I was also able to make a couple of runs down the Mornington Peninsula to drop miss-11 to a friend’s house (and pick her up again), and backed up the fuel use figures.

But as great a tourer as the GLS is, it isn’t perfect.

Using cruise-control in comfort mode automatically activates the lane-keep assistant, thus only requiring a light touch on the wheel, but on straight stretches of road the car regularly triggers a ‘hold on to the wheel’ warning.

On the flip side, if on country roads you need to move across the centre divider to pass a cyclist or potholes on the edge, and don’t indicate, the lane-keep aid will aggressively try to pull you back.

More crucially, the car will detect and slow for bends without your input, which can be a bit unnerving especially if you have cars following behind, as it tends to cut in quite sharply.
All these things are there to help and do work with you especially when you need them, but that line between driver assistance and control can become a little blurred. Proof again that we’re a long, long way from full self-driving.

As an aside, I also ventured off the beaten track in the GLS, and with the off-road mode on, where the car raises to its full height and changes the throttle, gearing and traction settings to handle difficult terrain, the big G didn’t skip a beat.

This wasn’t a competition trail or the Simpson Desert, but in a country where 80 per cent of the roads aren’t paved, it’s good to know you can drop off the black stuff without too much stress. Just ah, don’t get a puncture in one of those 22-inchers…

So in all, as far as a big, comfortable and hugely capable tourer goes, the 2020 Mercedes-Benz GLS450 is pretty jolly good. It can eat up plenty of miles on a long touring road trip all day, every day, and in fact, I would go as far as to say this is what it does best.

In the next update, I’ll go through all the technology and configuration parameters on offer, including the recently update Mercedes Me mobile application.

MORE: Long-term report one: Introduction
MORE: Long-term report two: Urban Living
MORE: GLS news and reviews
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