Mercedes S-class Cabriolet (2018) review

Published:02 December 2017

The new 2018 Mercedes-Benz S-class Cabriolet
  • At a glance
  • 5 out of 5
  • 5 out of 5
  • 4 out of 5
  • 5 out of 5
  • 5 out of 5

By Tim Pollard

Group digital editorial director, motoring news magnet

By Tim Pollard

Group digital editorial director, motoring news magnet

► New Mercedes S-class Cabriolet review
► 2018 upgrade brings in line with limo
► Extra engines, tech, priced from £116k

Everything that Mercedes-Benz knows about open-top motoring is squeezed into this new range-topper. The two-door Mercedes-Benz S-class Cabriolet and Coupe twins are being upgraded in line with the 2018 S-class four-door – bringing a host of engineering and specification upgrades to the luxury GT range.

So you get new engines and new badges (bye bye S500, hello to the returning S560 moniker), some spangly new features operated through widescreen 24in digital displays, more autonomous driving capability and a whole heap of extra performance.

We stayed behind after the 2017 Los Angeles motor show to test the new S-class duo across California’s mountains and highways. Read on for our full review of the convertible.

What’s new for 2018?

There’s a heart transplant for two of the three S-class soft-tops: the S560 drops the 441bhp 4.7-litre V8 for the 4.0-litre V8 bi-turbo. It’s essentially the non-AMG’ed version of the lump you’ll find in the C63/E63 et al, and here it produces 463bhp and 516lb ft of torque. Ample for an entry-level model.

The CAR magazine Mercedes S-class Cabriolet review, including specs, prices and performance figures

Meanwhile, the S63 AMG model keeps the name but swaps the outgoing 5.5-litre V8 twin-turbo for the more modern, full AMG-spec 4.0-litre V8, hand-built in Affalterbach and twinned with a new nine-speed AMG Speedshift auto. End result? A stonking 604bhp and 664lb ft of twist for some pretty scintillating performance figures.

Meanwhile, the top-dog 621bhp S65 AMG V12 continues mechanically unchanged. All models are distinguished by modest styling changes; spot the 2018 MY by its new front spoiler treatment (dubbed the ‘jetwing’ look), reprofiled side sills and new OLED rear lamps with 66 red rectangular slivers floating in the rear lights.

Finally, a digital update brings smarter semi-autonomous driving functions: the car will now steer for you more intelligently in cruise control and flick between lanes when you indicate (like Tesla’s system) and adapt the car’s speed itself, by syncing with map data and anticipating corners or speed limits ahead. Sounds creepy, actually works really well on well marked highways although we experienced a couple of auto-brake/steer false alarms caused by cars parked on the roadside.

Mercedes S-class Cabriolet: specs, performance figures and economy

You won’t want for performance in any model, frankly. The UK won’t take the S450 six-cylinder models (thinking being, the E-class Cabriolet and SL ranges cater for that market), so you’re restricted to picking from one of this brawny trio:

  • S560 4.0-litre V8 bi-turbo, 463bhp, 516lb ft, 4.6sec 0-62mph, 155mph top speed, 31.4mpg, 204g/km CO2
  • S63 AMG 4.0-litre V8 bi-turbo, 604bhp, 664lb ft, 4.2sec 0-62mph, 155mph top speed (186mph with AMG Driver’s Package), 28.8mpg, 225g/km CO2
  • S65 AMG 6.0-litre V12 bi-turbo, 621bhp, 737lb ft, 4.1sec 0-62mph, 155mph top speed (186mph with AMG Driver’s Package), 23.5mpg, 272g/km CO2

Burmeister stereo available on Merc S-class convertible. Prices from £116k

What’s it like to drive?

Any one of these soft-top S-classes provides serious grunt; even the slowest is as quick as many Porsches. Switch all the systems to Comfort and they’ll glide across back roads with effortless plump, the standard Airmatic air springs soaking up bumps, engines barely burbling; flick up through Sport and Sport+ and the chassis stiffens, the steering weights up and the transmission becomes more alert.

The changes wrought to the AMG twins make them impressively sharp for what remain big, heavy cars (the S65 tops out at 2.3 tonnes). They can be hustled along with surprising vigour and have an extra degree of agility over the comfort-focused, softer S560. It’s worth noting that all UK S-class Cabriolets will be rear-wheel drive only – the 4Matic models available elsewhere haven’t been engineered for right-hand drive, so we’ll miss the extra traction and 3.5sec 0-62mph times of the S63 AMG 4Matic.

Of the AMG twins, the V8-powered S63 is easily our pick. It is sensationally fast on a charge yet settles back to a relaxed gait when in Pacific Coast Highway cruising mode, and the snap, crackle and pop on downchanges in Sport and Sport+ mode (which opens the baffles on the sports exhaust) are hilarious. The S65 AMG is monumentally fast, too, yet feels less nimble, suffers from fuel consumption in the teens and is destined to remain a niche sight on our roads. After an evil V12 cackle at start-up, it’s barely any more sonically pleasing than the Jekyll and Hyde, raucous/refined S63.

Mercedes-Benz S-class Cabriolet with roof up

Electric operation of the roof is standard on every S-class convertible, as you’d expect, and the hood drops in 20 seconds at speeds of up to 40mph. It’s impressively refined in here and the triple-layer insulation means it’s exceptionally quiet with the roof up.

A techfest cabin

Step inside and nestle into some seriously plump armchairs. We dread to think how heavy these pews are, bolstered with a multitude of motors and gadgets to move every which way, to pummel your back with a choice of massages, warm your neck with Airscarf glow and hold you in place by inflating bolsters through sharp corners. They’re mega comfy and distinct chairs from those in the saloon.

The cabin shares the build quality and features of the S-class limo, and it’s hard to find fault with it. Yes, purists may yearn for less digital trickery but truth is the latest Comand system onboard (v5.5) is surprisingly simple to operate and you’ll quickly adapt. The precisely engineered air vents reflect the hewn-from-solid build quality (although they now seem a little last-season compared with the illuminating HVAC nozzles on the new CLS). 

Boot space is a modest 350 litres, but it’s about par for the sector and it’ll easily swallow weekend away luggage for two (there’s a ski hatch, too). And those rear seats are more than token efforts; six-footers will be comfy back there, there are Isofix car-seat attachments and occupants are protected from the worst bluster with the pop-up wind deflector.

How much does the 2018 Mercedes S-class Cabriolet cost in the UK?

The soft-top S will be priced thus, carrying a £12k premium over the S-class Coupe:

  • S560 Cabriolet £115,910
  • S63 Cabriolet £140,610
  • S65 Cabriolet £197,510

Understandably, mere handfuls of buyers will stump up two hundred big ones for the V12. This punchy pricing makes the S63 appear better value, although Merc points out that the premium is mostly taken up by extra optional equipment more than just a quartet of extra cylinders.

Burmeister stereo available on Merc S-class convertible. Prices from £116k

Order books are open now and first customer deliveries are expected in time for the new 18 registration in spring 2018.


This is a wonderful form of open-top transport in the truest grand tourer tradition. Any one of the S-class cabrios would make an excellent convertible for the well heeled, but it’s hard not to recommend the AMG S63. This is an astonishingly capable soft-top, with luxurious space for four, all the performance you could wish for and some extraordinary features that’ll pamper and cosset even the gnarliest of owners.

Some of the Italian or British competition might offer a dose more character and style, whatever that is, but we’d wager the engineering integrity and sheer breadth of ability of the Benz would make a smarter long-term prospect.

Read all our Mercedes-Benz car reviews here 


Price when new: £141,000
On sale in the UK: April 2018
Engine: 3982cc V8 bi-turbo, 604bhp @ 5500rpm, 664lb ft @ 2750-4500rpm
Transmission: Nine-speed automatic, rear-wheel drive
Performance: 4.2sec 0-62mph, 155mph, 28.0mpg, 229g/km CO2
Weight / material: 2185kg/steel and aluminium
Dimensions (length/width/height in mm): 5051/1913/1428mm


Photo Gallery

  • We drove the new Mercedes S-class Cabriolet in California
  • Roof down, the Merc S-class Cabriolet cuts a sleek profile
  • Note the new OLED rear lamps on the 2018 model year Merc S-class Cabrio
  • Huge twin 12-inch digital instrument packs ape those in the S-class saloon
  • Mercedes S-class Coupe (left) and Cabriolet arrive in UK dealers in April 2018
  • Roof up, the S-class Cabriolet is refined and nearly as quiet as the Coupe
  • New Energising Comfort mode allies heating, massage, lights and more to tailor your mood
  • The new 2018 Mercedes S560 Cabriolet: new entry-level model for UK replaces S500
  • Two-door Mercedes-Benz S560 Cabriolet, shot on location in California
  • A pair of new engines for the 2018 model year Mercedes S-class Cabriolet

By Tim Pollard

Group digital editorial director, motoring news magnet