From £57,6408
High-tech drivetrain makes for fast, interesting and engaging version of the CLS, if not quite the perfect one

What is it?

The shiny new Mercedes CLS has met with Mercedes’ shiny new mild hybrid drivetrain, with a real best-of-both-worlds brief.

The CLS 450 mixes a potent in-line six-cylinder twin-turbocharged 3.0-litre petrol engine with Mercedes’ new ‘EQ boost’ technology, comprising a 48V integrated starter generator and a lithium ion battery.

Sited between the engine and the nine-speed automatic gearbox (which drives all four wheels as standard), it not only provides the engine with an extra 22bhp and meaty 184lb ft of instant torque, but can completely switch the engine off in Eco mode when ‘sailing’, leaving the EQ boost to power the rest of the car’s ancillaries. Clever stuff.

The CLS 450 also presents our first chance to try Mercedes’ all-new big four-door coupé on the standard 19in alloy wheels filled with the noise-suppression foam, our earlier UK test being limited to the 400d version and its optional 20in wheels that made for a noisy and overly firm ride.

2 Mercedes benz cls 400 2018 uk review hero rear

What's it like?

The model name of our CLS 450 test car may end in ‘AMG Line’, but it feels more ‘AMG Lite’ in the way the engine propels it down the road. This is a very quick car indeed, with excellent traction off the line and from low speeds from the four-wheel drive system.

It’s at low speeds when you really feel the extra shove of the 48V system, yet the way it blends with the engine is seamless. That’s also true when you select Eco from the driving mode selector toggle and the car enters its sailing mode; you don’t notice it, and there’s not exactly a sonorous engine note to miss anyway.

In-gear performance isn’t as razor-sharp as off-the-line performance, the nine ratios being better suited for efficiency than outright performance in the way they’re tuned in this car, nor does it ever sound as good as it should do.

It would also be wrong to call this an economical car with such force under your right foot — more economical than it would otherwise be is more accurate — yet it also shows the potential of such tech. Here, the 48V system is primarily used for performance, but you can see how it could also be used for a primarily fuel-saving purpose. The powertrain was first used in the S500 in a higher state of tune, so the drip down the range in different tunes and purposes is already occurring. The future’s well on its way.

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After the powertrain, those 19in wheels interest most. While making for a quieter and more comfortable CLS, they can’t solve the harsh low-speed ride the CLS suffers from, particularly over road scars and potholes. Still, it’s a much more composed machine at higher speed and it's much better suited to fast, flowing roads than it is pottering in and out of the suburbs.

You’ll need to play around with the driving modes to find a CLS that feels ‘right’; our test car does without the optional air springs and adaptive dampers, and instead uses the standard steel set-up with selective dampers through different driving modes.

What the car really needs is a ‘normal’ driving mode between Comfort, which makes the car too fidgety and wafty and not sharp enough in its steering and handling, and Sport, which makes it feel too urgent and highly strung for everyday driving, particularly in the overly sensitive steering. Individual mode merely allows you to combine elements from other driving modes rather than offer anything more bespoke.

The rest of the experience is similar to that of our early drives in other third-gen CLS models; styling that’s better-looking than the second-gen Mercedes CLS (2011-2018) but not quite as pretty as the first, and an interior of the highest quality, comfort and usability (even if those steering wheel controls take some getting used to).

5 Mercedes benz cls 400 2018 uk review steering wheel

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Should I buy one?

Fast, luxurious, stylish, interesting and, at times, engaging, the CLS 450 has plenty going for it.

Yet it’s also a car that leaves you wanting more and asking, at times, what if. This is true of other versions we’ve tried, too.

This, then, is a very good version of the CLS, if still not quite a perfect one.

Mercedes-Benz CLS 450 specification

Where Berkshire, UK Price £57,640; On sale now; Engine 6cyls in line, 2999cc, twin-turbocharged petrol; Power 362bhp at 5500-6100rpm; Torque 369lb ft at 1600-4000rpm; Gearbox 9-spd automatic; Kerb weight 1940kg; Top speed 155mph (limited); 0-62mph 4.8sec; Fuel economy 36.2mpg; CO2 184g/km; Rivals Porsche PanameraAudi A7

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Mark Tisshaw

Title: Editor

Mark is a journalist with more than a decade of top-level experience in the automotive industry. He first joined Autocar in 2009, having previously worked in local newspapers. He has held several roles at Autocar, including news editor, deputy editor, digital editor and his current position of editor, one he has held since 2017.

From this position he oversees all of Autocar’s content across the print magazine, website, social media, video, and podcast channels, as well as our recent launch, Autocar Business. Mark regularly interviews the very top global executives in the automotive industry, telling their stories and holding them to account, meeting them at shows and events around the world.

Mark is a Car of the Year juror, a prestigious annual award that Autocar is one of the main sponsors of. He has made media appearances on the likes of the BBC, and contributed to titles including What Car?Move Electric and Pistonheads, and has written a column for The Sun.

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sumanrajput 19 May 2021

From the giant stacks of remarks on your articles,I brief I am not utilizing any methods, the only one having all the delight here. 

modside 3 April 2021
love this car it's my new favourite, I think the back end is gorgeous and its such a break from the old boring designs in my opinion!
jobstart 15 June 2020


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