Mercedes-Benz GLS (2021) Review
The GLS is the most luxurious – and capacious – Mercedes-Benz SUV. Now in its 3rd generation, the GLS needs to prove its worth against vaunted rivals, as well as some high-spec offerings from the Premium-SUV segment. We tested the petrol-powered GLS 580 to see if the Big Benz is as special as its price suggests…
We like: V8 power has its perks on the highway. Acres of interior space.
We don’t like: No real “wow factor” inside, jiggly ride at slow speed.
Fast Facts:
- Model tested: Mercedes-Benz GLS 580 4Matic AMG Line
- Price: R2 040 560 (R2 314 660 as tested)
- Engine: 4.0-litre V8 turbopetrol
- Power/Torque: 360 kW and 700 Nm
- Transmission: 9-speed automatic
- Fuel efficiency: 11.0 L/100 km (claimed)
- 0-100 kph: 5.3 sec (claimed)
- Top speed: 250 kph
- Load capacity: 355 (7-seater)/2 400 litres (all seats down)
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What is a Mercedes-Benz GLS?
The GLS is the S-Class of Mercedes-Benz’s SUV range. The biggest and most luxurious off-roader it offers.
Simply put, the GLS is the S-Class of the Three-pointed Star’s SUV range, the epitome of everything the German premium brand can offer in terms of luxury, tech and desirability in its biggest format – the 7-seater SUV. Direct competitors come in the form of the BMW X7, the full-fat Range Rover and the recently launched Land Cruiser 300, although the latter’s upcoming Lexus LX cousin (which will be based on the new ‘Cruiser’s platform) would technically be a more natural rival to the Benz.
These are behemoth SUVs, some 200–300 mm longer than Premium SUVs such as the Audi Q7, BMW X5, Lexus RX, Mercedes-Benz GLE, Range Rover Velar, Volvo XC90 models that usually tick the “big enough” box. Some of those are optionally available in 7-seater configurations, which, if you only occasionally need to seat small children right at the back, might be all that you need.
Under the GLS 580 4Matic AMG Line’s bonnet sits a turbocharged 4.0-litre V8, which is paired with a 9-speed automatic transmission and, alas, suffers from a petrol addiction that even a 12-step programme can’t break. There are 7 seats inside, all of which can be individually raised and folded away, while infotainment and connectivity are taken care of by Benz’s well-known MBUX interface.
How the Mercedes-Benz GLS fares in terms of…
Kerb- and road presence
The 22-inch optional wheels only just fill the wheel arches of the 5-metre-plus SUV.
There’s no doubt the GLS is a gargantuan SUV; it’s 5 207-mm long, 1 823-mm high and has a 3 135-mm wheelbase. You could very nearly fit an entire Peugeot 108 between the fore and aft wheels of the GLS – its wheelbase is that long. As you can deduce from these images, the AMG Line package endows the GLS with a bit more attitude thanks to the chrome strips on the front bumper and exhaust pipe surrounds, which are tied together by the matching side steps. The AMG Line also comes with what’s described as a “sporty engine sound” that ensures that the V8 under the bonnet makes itself heard.
It sounds a little daft, but the smallest wheels on offer are 20-inch alloys; the test unit was specced with 22-inch AMG M-Spoke alloy wheels (a R50 300 option), which fill the wheel-arches appreciably. To their credit, in tandem with the air suspension, they don’t diminish the GLS’ ride quality unduly.
By virtue of German premium marques’ slavish devotion to their respective design languages – Mercedes-Benz is no exception – it can be difficult to distinguish a GLS from a GLE or even a GLC from the front, but from side-on, the GLS’ extended length and heft easily set it apart as the “Big Daddy” in the lineup. Its badge appeal is likely to get the nod of approval from the “mink and manure” set.
Performance and, um, efficiency
The AMG Line comes with a “sporty engine” option that enhances the sound of the V8 under the bonnet.
The Benz’s 4.0-litre turbocharged V8 is effortlessly smooth… and refreshingly lazy. How could laziness be a good thing? Let us put it this way: too many modern (therefore, turbocharged) engines push out huge maximum power and torque figures, but do so in a rather spiky and abrupt manner; the GLS 580, by contrast, builds its way up the rev range smoothly, in a dignified manner.
Make no mistake: it’s not slow, by any means. If you stomp on the accelerator pedal, the Mercedes-Benz will swat away a Golf 8 GTI, but that’s not where the engine’s strength lies. The 700 Nm of torque available between 2 000 and 4 000 rpm promotes truly effortless in-gear overtaking. The motor feels strong and unstressed when it veritably sweeps past slower traffic.
If you plan to tow a horsebox (which, if you’re genuinely interested in buying a GLS, you probably already own) or that Riva Aquarama speed boat, the GLS 580 4Matic AMG Line is rated to tow a 3 500-kg braked trailer and has a trailer manoeuvring assistant, which, thanks to steering intervention, takes all the hassle (or potential embarrassment) out of reversing a trailer.
Take note that while the claimed fuel consumption figure of 11.0 L/100 km doesn’t seem that heavy, we could only make the test unit’s indicated figure dip below 12 L/100 km when cruising at 80 to 100 kph protractedly. We travelled quite a distance (1 200 km) with the Benz during its 2-week tenure in our test fleet. At the end of the evaluation, the GLS’ digital consumption readout indicated 13 L/100 km.
Interior elegance & practicality
The GLS interior is luxurious, but lacks a “wow factor” at this price point.
For various reasons, we have only had a chance to drive the GLS this year, even though the model was released overseas about 2 years ago. As a result, Benz’s top-of-the-range SUV doesn’t feature the latest and greatest interior as shown in the new S-Class, for example. In fact, its design/layout is a little too “copy and paste” – essentially a facsimile of a GLE interior with 2 additional seats in the rear.
The grab handles on the centre console, for example, are quite functional, but they’re straight from the GLE. The interior design can be mixed and matched via the options list to suit the style you prefer… The dash is clad in soft black leather, while the strip that runs the width of the cabin (and surrounds the air vents) can be specced in brushed aluminium, woodgrain, anthracite or even carbon-fibre look.
The MBUX infotainment system with its dual-screen “widescreen” setup is built into the fascia and, even now, some 6 years since its debut, it’s still the industry standard for clarity and graphics. Everything you need in terms of connectivity is built into the system although it would be nice to have wireless Apple Carplay and Android Auto connectivity instead of the plug-in setup (through the USB-C ports).
The interior doesn’t evoke wonderment in a manner you’d expect from something that’s meant to showcase “the ultimate in luxury”, but the GLS will likely receive the S-class interior when its facelift is due.
At 2 400 litres, you won’t find a bigger load space.
If you plan on ticking most of the options, which is probably the point of buying a GLS, you’ll get numerous nifty comfort features such as USB-C ports in every row and individual seat heaters. All the seats are electrically operated – via buttons on the seats themselves or in the load bay, but they can be a little slow to work if you’re just trying to access the 3rd row, where a manual switch would be much faster.
Passenger space is more than adequate in the 2nd row, even if you’re sitting 3 adults across. The 3rd row of seats is reasonably comfortable, but don’t expect to be able to stretch out. Even with all 3 rows up, the load bay can accommodate 355 litres (the same as a Polo hatchback), but with all the seats down it opens up a monumental 2 400 litres, even more than you’d get in a long-wheelbase Range Rover.
On-road refinement
On a wine farm’s dirt road – probably the place you’re most likely to spot a GLS.
As one would expect of a vehicle of this (considerable) size, the Benz can be a bit awkward to navigate within the confines of a city, such as on narrow streets. Out in the suburbs where the roads are wider, the GLS comes into its own. It’s very quiet inside, even though the GLS 580 4Matic AMG Line rolls on low-profile 22-inch tyres and wind noise is hardly noticeable, even when overtaking at 120 kph.
The air suspension works admirably well, but does jiggle about a little at slow speeds; it is almost as if it’s trying to make too many corrections to keep the body level, especially when the sizeable SUV turns into intersections or traffic circles (similar to the GLE we tested). The suspension proves a lot more neutral when the Benz sweeps through bends or hits its stride on the freeway. In fact, the GLS is surprisingly wieldy when it needs to negotiate a mountain pass in a hurry…. certainly more so than one would expect a vehicle of its size and heft to be.
You can flick through various drive modes to make the Benz’s chassis feel sportier, but we always defaulted to Comfort, as that was good enough when things got twisty without any of the extra suspension firmness that came with the Sport mode. After all, an S-Class-inspired Mercedes-Benz should be all about comfort, not so?
Mercedes-Benz GLS pricing & after-sales support
Don’t expect to find a bargain in the GLS range as pricing starts at R1.8 million for the GLS 400d and go as high as R3.2 million for the AMG GLS 63 4Matic+. The GLS 580 4Matic AMG Line retails for R2 118 460 (before options) and includes a 2-year/unlimited km warranty and a 5-year/100 000 km maintenance plan.
Verdict
The GLS is a very competent 7-seater SUV, but it falls short of deserving the title of “King of the SUVs”.
The Mercedes-Benz GLS will suit well-heeled buyers who want as much space as they can get in a luxury SUV. The interior space and, therefore, load capacity are as capacious as you can get at any price.
The turbocharged 4.0-litre V8 feels unstressed and accelerates creamily. It also helps that there’s a V8 burble to remind you (and everyone within earshot) that you’ve got some get-up-and-go in reserve.
The Benz’s interior, while plush and luxurious, doesn’t really feel special enough for a car that’s meant to wow at every touchpoint – after all, you have to part with in excess of R2 million to buy this derivative, yet its cabin can’t match the sense of occasion offered by the Range Rover and even the BMW X7.
The ride is tailored to cruising speeds where the suspension settles down and eschews some of the awkward wobbles it exhibits in town.
For now, the GLS doesn’t quite have enough going for it in the “razzle-dazzle” department to oust the exquisite Range Rover Vogue in outright appeal, but then… it is some R500k cheaper than the British offering. Is that’s something you want to tell people you chose a GLS for, though?


