2018 (18) Mercedes-Benz S-Class S350d L AMG Line 4dr 9G-Tronic

By Jonathan Crouch

Introduction

The Mercedes S-Class has always been the luxury saloon by which all others are measured. This improved version of the sixth generation 'W222'-series S-Class, an update launched in 2017, proved to be more affordable to run and even cleverer to use, but this car's real strengths continued to remain in comfort and refinement. This facelift may have represented a mid-term update but the changes were far-reaching. Under the bonnet, there were all-new petrol and diesel engines, the cabin was completely upgraded and there were further steps towards fully autonomous driving. It all added up to a package that continued to leave this as the world's best selling full-Luxury sector saloon. Let's check this model out as a used buy.

History

The Mercedes S-Class. It's traditionally been the sensible answer to the question every motoring expert likes to dodge - 'what's the best car in the world?'. Other vehicles can be more opulent, faster or better to drive but over the years, no other model has so consistently delivered such a technologically-advanced blend of automotive virtues. Here, we're looking at the vastly improved version of the 'W222'-series sixth generation model, an update Mercedes introduced in 2017. And we mean 'vastly improved'. Over 6,000 components were here either created or re-designed to change the 'W222'-series model (which had been originally launched back in 2013), creating this facelifted version. Which at the time made this the most comprehensive mid-life update made to any car in Mercedes history. You can see why the Stuttgart maker felt the need to do that, with completely new versions of BMW's 7 Series, Audi's A8, Porsche's Panamera and the Lexus LS all, by 2017, having been recently launched with jaw-dropping technology in a bid to tempt away traditional S-Class buyers. There are plenty of them because this car has such a long and distinguished history in the full-Luxury boardroom segment, known as the 'S-Class' or 'Sonderklasse' ever since this badging was first introduced on the 'W116'-series model of 1972. This updated MK6 model though, had a tougher brief than any of its predecessors. At its entry point, it had to satisfy successful top-level Managers, while at the other end of the line-up, the same design with greater power and opulence had to be also good enough to meet the exalted expectations of the Rolls Royce and Bentley buyers that the Stuttgart maker aimed to snare with its exclusive Mercedes-Maybach brand. To achieve all that, this car had to be ground-breaking in its period - but then the S-Class always has been. Models like this are state-of-the-art test beds for the best that their brands can produce. Some features will forever be limited to plutocratic purses, but many others will eventually filter down into the everyday mainstream - and there are plenty of examples of that. This, after all, was the luxury saloon that in 1978 pioneered anti-lock brakes, in 1981 introduced airbags, seatbelt pre-tensioners and traction control and by 1992 was the first car to be built entirely free from harmful CFCs. At its original launch in 2013, this 'W222'-series model had built on that with industry-leading hybrid engine technology and a super-clever anticipatory suspension system able to detect and respond to irregularities in the road ahead. In 2017 in this updated form, it was further embellished with the brand's latest autonomous driving tech, plus there was an all-new interior, a re-designed V8 petrol powerplant and, most importantly, a completely new 2.9-litre V6 engine for the S350d diesel variant that almost all S-Class buyers in our market chose. This car sold until the launch of the seventh generation 'W223'-series S-Class in late 2020.

What You Get

People all around the world can recognise an S-Class right away, its elegant styling ever an expression of luxury and the automotive grandeur of its era. Only subtle changes were required to update the look - and that's exactly what this revised model delivered. Most of these are found at the front where this revised 'W222'-series model featured freshly-designed 'Multibeam LED' headlamps incorporating a smart trio of daytime running light strips and featuring 'Ultra Range' high beams that operate at the maximum light output allowed by law. Between these, Mercedes added a revised and even more imposing radiator grille that favoured a simpler design with three chromed horizontal twin louvres. The vast amount of effort that Mercedes put into improving this 'W222'-series S-Class isn't immediately obvious from the outside but it certainly is once you take a seat behind the wheel. Other rivals from this period have superbly crafted cabins too, but none of them offer quite the same sense of opulent indulgence that you get here. As with the previous version of this car, the interior's dominated by a couple of 12.3-inch screens that are joined behind a single glass cover, one for the instrument binnacle, the other for the centre-dash COMMAND infotainment display. A change for this revised model was the addition of neat little smartphone-style touch pads on the smarter three-spoke Nappa leather-trimmed steering wheel. Plus there was an optional 'Energizing Comfort' package that co-ordinates various cabin features to create six pre-set relaxation programmes. Move to take a seat in the rear and you'll find that as at the front, the doors open very wide, especially if you've got the long wheelbase body style 80% of new buyers wanted, which is 121mm longer. What you'll find inside depends upon which of the rear seat packages the original buyer chose to specify. Standard models get a conventional three-person rear bench, but if you're looking for the long wheelbase body style that features across most of the range, it's quite likely that you'll want to find a car specified with the 'Individual Rear Seats package'. This gives you two separate chairs that are electrically operated and ventilated with opulent cushioned head restraints and a backrest adjustable by up to 37-degrees. Out back, boot space varies with the variant you choose. In the S350d, you get 510-litres.

What to Look For

Obviously buy with care - there are a lot of electrical features that could go wrong and you need to make sure that all the powered seat systems work properly and infotainment screen and instrument displays function as they should. Obviously, insist on a fully stamped-up dealer history and inspect the big alloy wheels for scuffs that could require a price reduction. There were a number of recalls for this model that you should be aware of. At one point in production, due to an issue with the wiring harness that sent an incorrect camshaft signal confusing the engine stop start system and causing it to cut out, some models had sometimes to be put in Park and restarted manually after coming to a stop. Some diesel models exhibited an automatic gearbox malfunction where the wiring harness controlling the gearbox was damaged by the hot exhaust, which made the car go into neutral at speed. And other recall issues? Well, there were reports of a rear seatbelt malfunction which saw the seatbelt extender in the back seat not retracting correctly when in use: check this on any car you inspect. There were also reports of an oil leak from the turbocharger, potentially leaking oil on to hot engine components; affected cars should have had a replacement oil feed pipe fitted as part of a recall. In some instances, some front passenger airbags weren't installed correctly; again, a recall sorted the problem and you should make sure that the car you're looking at has had it. There was also an issue reported regarding faulty software on the production line that saw the start stop system sometimes shut down. And there was an issue with the safety and emissions control system, which was fixed by a software update recall. In a few instances, there was a malfunctioning occupant safety system which saw the main power supply dislodged when the airbags went off, which then prevented various safety systems (including the automatic door lock release) to stop working. Make sure that the car you're looking at has had all of these things attended to. Replacement Parts

Replacement Parts

(approx based on a 2019 S500 - Ex Vat) An air filter is around £51. An oil filter is around £12. Front brake pads sit in the £173 bracket for a set (for rears it's around £215). A tail lamp is around £337-£351.

On the Road

On the move, you're reminded that there's still nothing quite like the serenity and elegance of an S-Class. By 2017 though, some rivals in the full-sized Luxury saloon segment were boasting superior under-bonnet engineering, hence the need for the biggest part of this sixth generation model's re-development budget to be devoted to fresh powerplants. The principal change was the replacement of the most popular S350d variant's aging 3.5-litre 258bhp diesel with a new-era 3.0-litre 286bhp unit. It was also available with 335bhp in an uprated S400d derivative. Mercedes directed just as much effort into improving its petrol proposition too, the alternative green pump-fuelled S500 featuring another brand new 3.0-litre 'six', this one putting out 457bhp and drawing on what Mercedes called 'systematically electrified' technology to simultaneously boost power while saving fuel. Another petrol engine new to the 'W222'-series S-Class, a 4.0-litre V8 with 612bhp, featured in the rejuvenated Mercedes-AMG S 63 sports saloon model. This variant is a much better bet than the far pricier S 65 derivative (which shares its 630bhp 6.0-litre V12 with the plutocratic Mercedes-Maybach S650 flagship variant). Whatever version you choose, there's the reassurance that you're in the most thoroughly-engineered Luxury saloon money can buy from the 2017-2020 period. Refinement is exemplary, the 9-speed auto gearbox is effortlessly smooth and for the most part, the standard air suspension dispatches road imperfections as if they didn't exist. Specified correctly, this model will drive for you, park for you and cosset you in a way that few cars at any price can. Autonomous driving capability was something that Mercedes particularly concentrated on improving with this revised 'W222'-series S-Class, the brand's technology embellished with navigational algorithms that anticipated traffic conditions and prepared the car in advance for roundabouts, corners and junctions.

Overall

This improved post-2017 version of the 'W222'-series S-Class spearheaded technological development in its period, not only for Mercedes-Benz but for the automotive industry as a whole - as the S-Class model line has done for decades. That kept this car very competitive with - and in some cases a step ahead of - more recently introduced Luxury segment rivals in its period. It can power to supercar speeds in AMG guise, deliver impressive economy in mainstream S350d diesel form and from new could be specified to eerily steer, power and brake itself at a cruise. Yes, other rivals may look more avant garde or handle with a touch more involvement. In overall terms though, Mercedes did enough here to enable this S-Class to remain a benchmark the kind of luxury saloon every prestige brand wanted to build in the 2017-2020 period. The best used car in the world? You'll feel like it is if you buy one.