Vast SUV delivers unbeatable practicality and wonderful refinement, but lacks the S-Class’s sense of occasion

The Mercedes GLS takes a huge leap on from its predecessor, boasting superb comfort and refinement while offering more space than nearly anything else for the money. Its diesel engine is smooth, powerful and quiet, delivering fuel economy which – though not great – is acceptable for this sort of car. We think E-Active Body Control is a must-have option to allow the GLS to operate at its best – the ride quality is sublime.

It’s not quite as special to drive or travel in as the similarly priced Mercedes S-Class, however – the dash looks too much like the cheaper GLE’s and refinement isn’t quite on the same level. It’s also huge; potentially too big for most UK roads and definitely for the city roads most will inevitably frequent. These nit-picks aside, the GLS is a great car overall.

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On its launch, Mercedes dubbed its GLS as ‘the S-Class of SUVs’. That’s a tough billing to live up to, especially when you consider the peerless reputation of the brand’s most luxurious saloon.

It’s made an even tougher task given the broad spread of abilities the GLS needs to cover. This is a car which needs to not only carry as many as seven adults in the sort of luxury that S-Class passengers would expect, but also give a decent account of itself off road – whether drivers ever bother to take it there or not.

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The GLS follows on from the previous model (which before a renaming strategy in 2016 was simply known as the GL), but this is possibly the closest to S-Class-on-stilts travel yet. It also sits at the top of a huge Mercedes SUV family, which kicks off with the GLA and climbs through to the GLB, GLC and GLE (the latter two are also available in sleeker ‘Coupe’ model lines), the iconic G-Class and all-electric EQC.

While the previous GLS platform could be followed all the way back to 2005 and the M-Class SUV, the current model shares it underpinnings with the latest GLE. With a structure that’s both lighter and more rigid than before, it helps Mercedes to deliver superb refinement. It also enables the brand to install the latest and fanciest version of its MBUX infotainment system, a host of advanced safety tech.

The single engine option is strong and refined, while comfort is exceptional – with the right options selected
This is a big, heavy car; even with a capable diesel engine it will cost a pretty penny at the pumps
Cabin is well finished and packed with brilliant tech, but it doesn’t quite feel special enough for the price
The GLS is the most spacious posh seven-seater on the market – but its vast size will cause headaches on the road
A brilliant safety rating is all but guaranteed, but Mercedes ownership prospects are below average

The GLS family kicks off with the AMG Line Premium trim. Standard kit includes 22-inch alloy wheels, a 360-degree camera and a panoramic sunroof. Above it sits the AMG Line Premium Plus: it costs £5,250 more, adding augmented-reality navigation, massaging climate-controlled front seats, heated front and rear armrests.

There’s only one engine: a 3.0-litre V6 diesel matched to a nine-speed automatic gearbox. Expect more models to join the lineup in future, including the possibility of a hot AMG version.

There’s one car that Mercedes has clearly pitched itself towards: the BMW X7, another imposing SUV that delivers space and refinement for up to seven people. The Range Rover Sport is also similarly matched on price, but it can’t compete with the Merc’s rear seat space. Above the GLS price-wise – but unable to match its seating count – are the Bentley Bentayga and the Rolls Royce Cullinan.

Last updated: 
13 Sep, 2019