Mercedes-Benz S 350d 2018 Review

Mercedes-Benz was among the crystal ballers. Back in the late ’90s the German marque undertook a huge increase in model ranges and a major shift in its approach to selling premium cars.

Mercedes-Benz today offers cars ranging from lumbering SUVs right down to small hatches. However, one thing hasn’t changed. The pinnacle Mercedes-Benz is still – after all these years – the S-Class sedan.

The 2018 S-Class update has been given more than new window dressing (you can read about all the improvements here).

The most significant of these changes is improvements to the S-Class’ driver assistance package, in particular its step up to Level two ‘hands off’ autonomy.

A new feature called Active Lane Change Assist will steer the car into an adjacent lane when active cruise control is engaged and you flick the indicator on (at speeds of 80km/h and above).

The system will ‘look’ for a space in the adjacent lane for up to 10 seconds (the current E-Class, the only other ‘Benz with ALCA, is activated for only two seconds) and when it sees the lane is clear, move over. This of course still means that you have to hold onto the steering wheel – as is required under Australian law. ALCA worked well on our drive, guiding the 2000kg-plus sedan seamlessly into the next lane while I lightly held the steering wheel.

The S-Class’ Active Steer Assist  is also new for MY18, and it help keep the car within its lane (when the DISTRONIC Active Proximity Control - active cruise control - is activated). While ASA helped guide the car on straight roads with clear lane markings, it only works on ‘mild bends’, according to Mercedes-Benz. That is certainly true; the bends have to be very mild or the S-Class’ will start to veer towards the lane markings. This technology doesn’t pretend to be level three - ‘eyes off’ autonomy though..

While ASA helped guide the car on straight roads with clear lane markings, it wasn’t so helpful on curves. Even when following a line of traffic on a clearly marked secondary road at 60km/h, the system didn’t want to guide the car around the corner. If this system is a preview of what is coming in higher levels of autonomy, it certainly has a way to go yet.

The S-Class' DISTRONIC active cruise works well on our 300km drive, although on its closest distance setting, it feels like you’re sitting a bit too close to the car in front. Bump it back to the next setting and it manages a more appropriate distance and gets on the brakes early and smoothly when approaching slow traffic ahead - unlike some active cruise systems.

The big Merc also gets traffic sign recognition for 2018 (Traffic Sign Assist), and with the ever-changing speed limits in Australia this is a great feature. Of course, it’s only as good as the signage present and there’s a question mark over whether it can read temporary LED roadworks speed signs.

Pulling out of Melbourne Airport straight into 80km/h roadworks, the S-Class was telling us that we were in a 110km/h zone. It was only later when we reached a 100 sign did it change its mind.

New engine a highlight

A headline feature of the entry-level S 350 d is its new 210kW/600Nm inline six-cylinder engine. It provides smooth and strong acceleration with only a small amount of lag at low revs.

The diesel is a sweet, free-revving unit that combines well with a slick nine-speed auto. While we couldn’t squeeze out an economy figure close to the claimed 5.4L/100km average, the 7.1L/100km figure showing on the trip computer wasn’t bad for a big, heavy car.

The engine teams with air suspension that manages to contain body motion and iron out the bumps really well. The S-Class is one smooth-riding car, although it doesn’t absorb big hits such as potholes quite as serenely.

Elsewhere, the S-Class has a quiet and comfortable cabin, with only a distant rustle from the side mirrors when cruising at 100km/h. Engine noise – even when the diesel six is revved up to its 4500rpm upshift point - is muted.

The high-res widescreen cockpit display is simply brilliant. It displays umpteen information simply and clearly. Using the central controller for infotainment functions is also logical and easy.

The S-Class has finally lost a Mercedes feature going back to the W124 E-Class, if not before. The cruise control stalk has been replaced by steering wheel buttons. The new set-up is easy to use, although there was nothing wrong with the stalk except it was old fashioned and couldn’t easily accommodate the new active cruise functions.

Mercedes-Benz reckons that drivers will feel the serenity even more with a new S-Class feature called Energising comfort control. Standard on the S 560 and up (or a $1400 option on other models) there are six settings that change air-conditioning, seat heating/cooling (and a massage function) and music to suit the mood chosen - from upbeat to relaxing.

While this feature is meant to wick some of the stress out of S-Class occupants, Mercedes-Benz might need to revisit the massage function. It felt as though I was being randomly prodded in the back. The lumbar support, however, is one of best I’ve tried, and the seats – other than when activating the massage function – are very comfortable.

The guts of the S-Class’ engineering is as good as ever – it’s a super-quiet, smooth and refined luxury cruiser. Yet much of this new model is about introduction of clever technology. Some of it is very good – the Active Lane Change Assist for example, and even elements of the Energising comfort control (such as the choice of music, either selected from your own USB or the audio system’s hard drive to suit the mood). Traffic Sign Assist could be better though; while the future is promising for such a feature, it needs more development – with infrastructure or otherwise - to be something that you can rely on.

2018 Mercedes-Benz S 350 d pricing and specifications:
Price: $195,900 (plus on-road costs)
Engine: 2.9-litre six-cylinder turbo-diesel
Output: 210kW/600Nm
Transmission: Nine-speed automatic
Fuel: 5.4L/100km (ADR Combined)
CO2: 141g/km (ADR Combined)
Safety Rating: Five-star ANCAP

Also consider:
>> Audi A8 (from $198,855 plus ORCs)
>> BMW 7-series (from $222,100 plus ORCs)
>> Lexus LS460 (from $185,691 plus ORCs)