Mercedes G-Class review

If you’ve flicked through a celebrity magazine or visited Harrods recently, the Mercedes G-Class will be on your radar. This square-sided luxury SUV – nicknamed 'the G-Wagon' – is a big hit with the rich and famous.

Mercedes first launched the G-Class in the Seventies, and it was developed as a military vehicle that could go almost anywhere. The G stands for Geländewagen (German for ‘cross-country vehicle’) and it's incredibly competent off road. 

There have been quite a few big updates to the model over the years, but at a glance, a new G-Class doesn't look all that different to an early one. This is still very much an old-school 4x4, with rugged suspension, a separate chassis and a high centre of gravity.

It's much pricier than your average 4x4, though. While you could think of it as a teutonic alternative to the Land Rover Defender style wise, the G-Class actually costs about the same as the Range Rover or a heavily optioned BMW X7.

Fortunately, beneath the utilitarian exterior, you'll find the sort of luxury you'd expect in a car with a six-figure price tag. There's swathes of leather, a modern infotainment system and all the clever driving tech Mercedes can throw at it.

For even more power, you can get a G-Class with AMG tuning and a V8 engine, the Mercedes-AMG G63.

If the idea of this most iconic of luxury SUVs appeals, read on over the next few pages of this review to find out how our road testers rate it in all the important areas – from performance to practicality.

Once you've decided on the new car for you, remember we can save you thousands off the list price if you search our free What Car? New Car Deals service. It has lots of the best new luxury SUV deals.

You get a choice of two engines for your Mercedes G-Class: a sensible 3.0-litre six-cylinder diesel in the G400d or, if you really want to push the boat out, a 4.0-litre V8 with a pair of turbochargers in the AMG-fettled G63.

Despite this huge SUV weighing at least two and a half tonnes, the diesel is as much engine as most drivers will need. The 0-60mph time of 6.3sec in our tests narrowly beats the more powerful Range Rover D350, and with plenty of pull from low in the rev-range, accelerating up to motorway speed is easy.

The G63 offers an exciting turn of pace for something this tall and bulky. Any car that can whizz from 0-62mph in 4.5sec is impressive, but the fact that this boxy luxury SUV can do so feels even more of an achievement. It's accompanied by an appropriately theatrical soundtrack from the engine and the exhaust, which is mounted down the side, ahead of the rear wheels. 

While both offer fast acceleration in a straight line, if you try to use too much power while turning, you’ll have the stability control light flashing away. The G-Class’s high ground clearance and soft suspension are great on the rough stuff but hurt its handling.

It's worth pointing out that the latest G-Class represents a huge step forward for ride and handling compared with its predecessor, but grip is in relatively short supply around corners. Even with wide tyres and the adaptive suspension, the stability control is quick to intervene.

The tall, heavy body pitches in bends noticeably, and the G400d feels ever more cumbersome the harder you push. When you try to thread it down a twisty road with gusto, body lean becomes even more pronounced. A Range Rover still leans in the corners, but it feels more capable than the G-Class, flowing from corner to corner with plenty of grip. 

Another thing you’ll notice when you start driving is how slow and heavy the steering is, and how many corrections you have to apply to keep it in a straight line. The Range Rover’s quicker steering response makes it more effortless to place on the road, but keener drivers may want to consider the BMW iX if they want sharper and more feelsome steering from their luxury SUV. The large turning circle on the G-Class also makes low-speed manoeuvres more tricky than most rivals.

Plus, if you put your foot down from a standstill, there’s a long hesitation before the G-Class accelerates away as the nine-speed automatic gearbox fumbles to find the right gear. It shifts through gears smoothly once you’re on the move, though. 

This isn't an especially smooth cruiser, despite having adaptive suspension. The live rear axle – a set-up that incorporates the car’s driveshafts and differential in a single rigid unit – causes the car to jostle and heave around on scruffy road surfaces. Your head will be thrown around on undulating country roads even in the suspension’s comfiest setting.

The G400d feels very much like a well-sorted pick-up truck on the open road – which is no surprise, as it has the same basic lay-out as the Mercedes X-Class. That said, while the ride and handling isn’t great by the standards of the luxury SUV class, that's missing the point somewhat, because the G-Class has always been a rugged 4x4 in the old-fashioned sense.

Indeed, a low-range gearbox, differential locks and long suspension travel mean it really is very capable in the rough stuff, aided by the freedom of movement of that live rear axle. Even if you’ve bought one with no intention of scuffing its expensive alloy wheels doing something as crazy as driving it off road, it's good to know that if you need to, it can.

Engine noise in the G400d is well subdued, while the V8 engine in the G63 generates a faint theatrical rumble in the background. There's noticeably more road noise in the G-Class than in most luxury SUVs and that bluff windscreen generates quite a high amount of wind noise at motorway speeds.

Few will have trouble getting comfortable behind the wheel of a Mercedes G-Class. The steering wheel, seat and pedals all line up nicely and there’s a reasonable amount of room for your left foot.

Electric seats with a memory function are standard, with the basic controls mounted on the doors. You’ll have to dig into the infotainment system to adjust the lumbar support or activate the optional massaging seat function that comes as part of the G Manufaktur package. That option pack also upgrades the seat's side bolsters so they actively tighten up in the corners to keep you upright. 

Once you're settled behind the flat-bottomed steering wheel, you’re greeted by a pair of 12.3in digital displays – one for infotainment and one in place of conventional dials. Both are configurable and easy to read, with pin-sharp graphics.

The infotainment system is primarily controlled using a rotary dial between the front seats. There’s also a touchpad you can use to enter 'handwriting' (when entering addresses into the sat-nav, for example), but it can be fiddly to use when driving.

The dash has more buttons than in a lot of luxury SUVs and most are incredibly useful. The air-con controls save you from needing to delve into a touchscreen menu, as you have to in the BMW iX, although the low placement of the clock and shortcut keys make them a little tricky to read.

Alternatively, you can use the touch-sensitive pads on the steering wheel – the left one controls the infotainment and the right one controls the dials. They can be a bit annoying, though. Unintentional contact can cause the infotainment system to change radio stations or the selected panel of information on the trip computer.

The interior of the G-Class feels sturdier than in many rivals, giving the impression that it can withstand journeys involving rough terrain. There’s plenty of soft leather and attractive finishes, so it doesn’t feel at all utilitarian. The extended leather option of the G Manufaktur package gives it an even plusher feel.

As is so often the way, the Mercedes G-Class has grown larger as it’s grown older. The current model has been made longer and wider to offer more room for passengers and their luggage. Despite being narrower than many rivals, including the Range Rover, there’s more than enough width to stop you bashing elbows with your passenger, and there’s tonnes of head room, even with the electric sunroof fitted.

In the rear, space is fine for adults, but it’s far from outstanding in the luxury SUV class (after all, the G-Class has to compete with the Bentley Bentayga and the Range Rover). Shoulder room is where you'll find the biggest compromise. There's enough for two broad adult occupants, but unlike in the G-Class’s luxury rivals, fitting in three will be a squeeze.

Rear-seat head room is still plentiful, though – that tall, boxy shape means occupants can wear top hats if they feel like it – and leg room is adequate. There's a small hump on the floor, but it’s not big enough to force  the middle rear passenger to straddle it.

Seating flexibility is fairly standard. Most rivals offer a more versatile 40/20/40 split, rather than the 60/40 format used in the G-Class, and the BMW X7 and the Range Rover have seats that fold electrically. Still, the seat base in the G-Class lifts up, so the backrest sits flatter than the one fitted in the Range Rover.

The 667-litre boot (much bigger than the Bentayga’s but some way short of the one in the Porsche Cayenne) means there should be enough room for all but the biggest Harrods shop. If you’re after a seven-seat luxury SUV, you’ll need to look at the X7, or the long-wheelbase Range Rover.

There’s no denying that the hand-built Mercedes G-Class is expensive to buy, finance and run. The cheapest diesel version has a high five-digit price that’s higher than the Range Rover and BMW X7 while the top-spec G63 Magno Edition will cost you more than two Audi SQ7s.

At least the G400d comes in AMG Line Premium Plus trim and is packed with equipment. That includes 20in alloy wheels, ambient lighting, three-zone climate control, front and rear heated seats, a Burmester stereo, a panoramic roof, 360-degree parking and adaptive suspension.

The optional G Manfaktur package costs just under £8000 and adds massaging seats and extended leather. The AMG G63 adds AMG body styling, including 22in wheels, colour-coded brake callipers, a sports exhaust and a sportier front grille design. Carbon and Magno Editions simply add different interior trim finishers and darker exterior highlights.

The G-Class holds on to its value very well, and the G400d loses less to depreciation than the equivalent Range Rover over four years of ownership.

As for fuel economy, the diesel manages just 25.7mpg in official tests, which is not very good, although during our time testing it we easily beat 30mpg. That still trails the equivalent Range Rover, with its mid-30s figure, though. The G63 is even more punishing, with an official figure of 17.7mpg.

CO2 emissions for the G400d are an eye-watering 289g/km (although that’s nothing on the 363g/km of the G63), easily placing the G-Class in the top bracket for first-year road tax and benefit-in-kind company car tax. 

You get plenty of safety kit as standard, including blind-spot monitoring, automatic emergency braking (AEB), lane-keeping assistance, road-sign recognition and adaptive cruise control.

Euro NCAP gave the model its full five-star rating, although it scored less points in specific categories than some luxury SUVs, including the Volvo XC90. Chest protection for front occupants during a frontal impact, in particular, was deemed as weak.

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