Mercedes-Benz S 350 d review
The modestly facelifted Mercedes S-Class debuts the company’s sensational new diesel engine in the S 350 d model.
Shane O' Donoghue
Shane O' Donoghue

Published on December 12, 2017

Good: classy appearance, high-quality interior, exceptional engine

Not so good: options are expensive

I must admit that the debut of the updated Mercedes-Benz S-Class earlier this year barely registered a blip in my important-news-o-meter. After all, the visual updates were minimal. On the outside, all versions of the S-Class get a new design of front grille and there are impressive new Multibeam LED headlamps with what Mercedes calls 'Ultra Range High Beam'. These feature automatic dipping and dimming, and they alter the beam shape depending on vehicles ahead and oncoming traffic. It works very well and comes with a sci-fi like start-up sequence you won't tire of. The rear lights, also LEDs, have been restyled slightly, as has the rear bumper and exhaust outlets.

Our test car was the AMG Line version, so it benefits from a subtly sporting body kit including the bumpers and side sills. A set of 19-inch AMG alloy wheels are standard, too, though optional 20-inch items (at €1,419) are pictured. Speaking of options, that classy Iridium Silver Metallic paint is €1,874 and the panoramic sliding sunroof is an eye-watering €2,743 extra. That's a shame, as it works particularly well with the silver paintwork.

The glass roof also allows more light into the luxurious cabin of the S-Class. It really is a gorgeously appointed interior with loads of high-quality materials throughout and a design that, while obviously related to other Mercedes cars in the line-up, is still different and special enough to grace the range-topper. As part of the updates for this year, the two high-resolution display screens are now behind a single smooth glass cover and it looks very impressive. What's more, the new steering wheels (lovely to hold, but oddly using plastic for the spokes where metal would fit the S-Class image better) feature the highly intuitive thumb touchpads that debuted on the Mercedes E-Class, allowing incredibly quick and easy access and navigation of the considerable number of sub-menus available. The display itself can be customised to a certain extent, too.

There's plenty of storage in the cabin, including a massive covered bin under the centre armrest that comes with a cleverly designed lid, as it can be opened from either side of the car. The rear seats are comfortable and come with their own vanity mirrors, though if you're buying an S-Class to sit in the back, you should consider upgrading to the long wheelbase variant.

One of the most significant changes to the big Mercedes is the introduction of a new range of engines and the big news is that V6 powerplants are out, in favour of inline units. There are two diesel models, both using the same core 3.0-litre straight-six, the S 400 d (340hp/700Nm) and the entry-level version tested here, the S 350 d. Believe me when I say that there is no reason whatsoever to go for the more powerful unit. The S 350 d's engine puts out 286hp and 600Nm of torque, which is more than ample on paper and also in reality, where it effortlessly fires the big S-Class down the road, making it feel far lighter than it should. What's more, it's silky smooth while doing so, noticeably quieter and more refined than the V6 diesel of old. Not that you ever need to rev it, but if you do you're greeted by a pleasing (but still distant) six-cylinder sound. Likewise, there's rarely any reason to use the tactile metal-like paddles behind the steering wheel to take manual control of the nine-speed automatic transmission as it's perfectly judged, with soft gear changes throughout.

Job done, right? Except the S-Class isn't finished impressing. If you deign to toggle into Dynamic mode, the gearshifts speed up a little, the throttle response sharpens up and so does the power assisted steering. The suspension, featuring adaptive damping and Airmatic air springs as standard, adjusts too, and you'd be surprised at how agile and willing the standard wheelbase S-Class can be, even if the low-speed ride quality is compromised a tad in this guise. Thanks in part to the variable ratio steering, it really does shrink around the driver and is far more engaging than any luxury saloon has any right to be. I'd go so far as to say it's at least as good to drive as the current BMW 7 Series.

The S-Class is best kept well within the limits of adhesion, where it's incredibly capable and composed, as rear wheel scrabble is unseemly. Saying that, even in cold and wet weather, the Pirelli P Zero tyres were finding good grip and traction, giving the driver loads of confidence to use the considerable grunt of the engine. The ESP stability system is very quick-acting as well. Switch things back to the Comfort mode and serenity is restored. The air suspension works particularly well at speed and it's incredibly comfortable on the motorway. What's more, the chassis can eerily isolate its occupants from the outside world over most surfaces, even in the wet.

Unless something drastic changes in our tax system, most examples of the S-Class sold in Ireland will be powered by diesel for the foreseeable future. Prices for the S 350 d start at €90,880, or €97,385 for the long wheelbase (LWB) model, and both are offered in standard and AMG Line specifications. Some of the embassies will no doubt choose from the petrol options, of which there are plenty, from the S 450 and S 500 powered by a new 3.0-litre inline six-cylinder unit to the V8-engined S 560 (offered in Mercedes-Maybach guise, too) and even a V12 in the S 600. The ultimate performance models are the Mercedes-AMG S 63 4Matic+ and S 65.

But it's testament to the excellence of the entry-level diesel engine that we reckon that the pick of the range is this new S 350 d variant. As luxury cars you like to drive yourself go, it's very hard to beat.


Tech Specs

Model testedMercedes-Benz S 350 d AMG Line
Pricing€108,818 as tested; starts at €90,880
Engine3.0-litre straight-six turbocharged diesel
Transmissionnine-speed automatic, rear-wheel drive
Body stylefour-door saloon
CO2 emissions139g/km (Band B2, €280 per year)
Combined economy52.3mpg (5.4 litres/100km)
Top speed250km/h
0-100km/h6.0 seconds
Power286hp at 3,400-4,600rpm
Torque600Nm at 1,200-3,200rpm
Boot space510 litres
Rivals to the S 350 d