Mercedes-Benz GLS review

A chuffing massive Mercedes, is what it is. Launched back in 2019, this third generation is longer and wider than ever. The “S-Class of SUVs” (Merc’s words) is quite possibly one of the biggest cars on sale in the UK. So long, you can almost fit a whole Fiat 500 just in its wheelbase, not to mention the contents of several C-Class Estates in its interior.

It is truly gargantuan and verging on just too enormous for our towns and cities. Certainly won’t fit through a 6ft 6in width restrictor, or in your local NCP. Drive it through the Eurotunnel and you’ll need to ride with the coaches and caravanists instead of the other cars.

And yet, there are still plenty of rivals. Think BMW X7, full-fat Range Rover or the larger-still Land Rover Defender 130. An Audi Q7 or Volvo XC90 would be a slightly smaller and more affordable choice.

Hit me with some history,

Wasn’t always called the GLS. A while back Merc’s biggest SUV was just the GL - then the company played around with its naming structure, adding the extra letter in 2016 to reflect this is the S-Class to the GLE’s E-Class, GLC’s C-Class and so-on.

At the launch of this latest generation back in 2019, Mercedes told us it had shifted more than half a million examples of the two previous versions, with a fair chunk of those sales in the United States. Which, as it happens, is where it’s built (alongside the GLE in Alabama), and amusingly, where it feels no less compact and wieldy than a Ford Fiesta does in West London.

How many seats does it have?

The trade-off for the GLS’s general massiveness is interior space - like its rivals, the GLS is as enormous inside as it is outside, with space for seven fully-grown adults and all their things.

Wasn’t there a facelift recently?

Great knowledge of Mercedes-Benz product cycles. Gold star for you. Merc actually refreshed all of its SUVs in 2023, with the GLS treated to a new grille with chunkier horizontal bars, a new front bumper and a revised rear light signature.

A light update, it also included new wheels, a new steering wheel, different colours for the leather inside, fresh exterior paint options and tweaks to the MBUX infotainment system. More on that over on the Interior tab of this review.

What engines can I have?

In the UK, the entry level GLS is the 450d in AMG Line Premium Plus trim. That’ll set you back £110,800 before options and is equipped with a mild-hybrid 3.0-litre straight-six diesel that makes 362bhp and 553lb ft of torque. Next up is the 450 petrol, which also uses a mild-hybrid straight-six but will see you filling up from the green pump. That makes 376bhp and 369lb ft of torque and also gets a little bit of mild-hybrid assist. Prices start at £114,180.

Want more grunt? You’ll be needing the £150k+ AMG GLS 63 4Matic+ Night Edition complete with its 4.0-litre twin-turbo V8. That results in 604bhp and 627lb ft of torque, while also featuring a teeny little bit of mild-hybrid assist.

All GLSs get Merc’s 4Matic all-wheel drive system.

Isn’t there a ridiculously posh Maybach version?

Ah yes, we’d hoped you’d forgotten about that. The Mercedes-Maybach GLS 600 gets a monstrous chrome grille, Maybach logos in the air intakes, optional 23in forged wheels and either a four- or five-seat layout. Because yes, it’s all about sitting in the back.

There is still a version of that hybridised 4.0-litre V8 up front though, which means 550bhp and 538lb ft of torque. Oh, and it weighs a frankly terrifying 2,825kg.

Surprise, Surprise – big Mercedes is rather excellent. The GLS is a massive car inside and out – families will love it for its practicality, although the driver might not be so keen on parking it in the UK.

The fact you can fit adults comfortably in the third row, and a decent amount of luggage behind them, is a real plus though. A tremendous long-distance cruiser, with comfy seats and great engines. Also isn't anything like as obnoxious to look at as its closest competitor, the BMW X7.

Assuming you get on with the infotainment and aren't intending on driving this thing quickly, our only real criticism is that it should perhaps be posher still inside. For that you now have to buy the Maybach version, and we’re not sure anybody should feel completely comfortable making that kind of statement.