It feels like Mercedes has been taking a long time about launching its new G-Class. Yet now it’s finally here, it feels like we’ve been sent the pictures of the old one by mistake.

But perhaps we shouldn’t be surprised it looks so similar: despite being close to its 40th birthday, sales have improved year after year of late. The G’s more successful than ever.

“Our main focus was on increasing the vehicle rigidity and the connections between the suspension and drivetrain with the ladder-type frame,” says Merc’s off-road car boss, Dr Gunnar Güthenke.

Not the styling, then. So while there are new LED lights (which arguably look a little aftermarket), all the G-Wagen hallmarks are present and correct: exposed spare wheel, prominent indicator lights, protective exterior strips, and so on.

Work’s been done to make the wheel arches and bumpers “look less like add-on features”, but we’re hard pushed to spot the difference. While Merc has worked on closing up the panel gaps, it says it’s kept the endearingly old-fashioned, “characteristic closing sound” of the doors.

The G is up to 170kg lighter than before, but a bit bigger – 53mm longer and 121mm wider – which has apparently benefited interior space, always a bugbear in the somewhat inverse-Tardis old car. The passenger’s dashboard grab handle stays, as does the driving position that puts your face right in the windscreen. Seeing how the G-Class performs in crash tests may be interesting.

Otherwise, it’s all very modern inside. The dashboard is far more up-to-date, while the seats can offer massaging, heating and cooling. The dials are all digital (and highly configurable) while the media system gives haptic and audio feedback as you twiddle its controls. Read more about the interior of the new G-Class here.

The G-Class launches as a G500, with a twin-turbo 4.0-litre V8 providing 416bhp and consuming a claimed 25mpg. It’s linked to a new nine-speed automatic gearbox. Other new-fangled stuff comprises electric steering – bringing self-parking tech with it – and adaptive dampers that help you traverse off-road stuff.

Indeed, the G-Class hasn’t forgotten its roots. It still uses a traditional ladder-frame chassis, three differential locks and low-range gear reduction. The ground clearance is better than before, improving the G’s already formidable wading depth and approach and departure angles. Only now, should you prod the right drive select buttons, there’s a bit of modern tech to help soak up tough terrain.

UK prices haven’t yet been announced, but in the G-Class’s native Germany, the G500 will start at a whisker over 107,000 euros, which converts to around £95,000. It’ll still be a pricey thing, then, only there’s now more plushness to back it up. Deliveries start in the summer.

Over to you, then. Should Mercedes have been a bit braver? Or is this an object lesson in how to refresh an icon – one Land Rover should be taking note of for the Defender?