Skip advert
Advertisement

New Mercedes SLC 300 review

The Mercedes SLK is reborn as the SLC roadster but is its folding hard-top refinement enough to beat the Boxster and TT?

Find your Mercedes SLC
Compare deals from trusted partners on this car and previous models.
Or are you looking to sell your car?
Value my car
Fast, no-nonsense car selling
Value my car

The SLC 300 offers a strong blend of performance and economy wrapped up in a stylish exterior. The problem is that the rest of the package is feeling its age. Minor updates can’t disguise that rivals feel sharper to drive, and the ride isn’t as smooth as it should be. An Audi TT Roadster is a better all-rounder, and cheaper to buy. Perhaps surprisingly, the SLC 250d actually makes more sense.

Advertisement - Article continues below

We’ve already tried Mercedes’ new SLC (a mildly updated and rebadged SLK) with a diesel engine and in left-hand drive. While undoubtedly frugal, and set to be the most popular SLC variant, the oil-burner isn’t going to cause sleepless nights over at BMW or Porsche. So, now we’re putting the two-door roadster through its paces with, what should, be a more exciting 2.0-litre turbocharged petrol engine.

Visual updates over the old SLK aren’t huge at first glance. It’s most noticeable at the front end, where there’s a redesigned bumper and a sharper diamond grill design. Flagship AMG-Line spec brings with it a subtle bodykit, lower sports suspension and multi-spoke 18-inch alloys, too. Small changes they may be, but there’s no denying that the SLC is a pretty little roadster as a result. 

Skip advert
Advertisement
Skip advert
Advertisement - Article continues below

Used - available now

Juke

2023 Nissan

Juke

17,306 milesAutomaticPetrol1.6L

Cash £17,399
View Juke
Crossland

2024 Vauxhall

Crossland

20,896 milesAutomaticPetrol1.2L

Cash £13,397
View Crossland
Civic

2021 Honda

Civic

47,992 milesManualPetrol1.5L

Cash £13,197
View Civic
Golf SV

2020 Volkswagen

Golf SV

32,254 milesManualPetrol1.5L

Cash £12,997
View Golf SV

Best sports cars to buy now

If you owned an SLK you’ll get déjà vu stepping inside, too. Plusher materials on the dash and doors give it a more high quality feel than before, and it’s a comfortable place to sit. Yet, the layout is broadly the same as the old car, and as a result it feels decidedly dated next to the Audi TT’s slick cockpit. Details like the fiddly numeric keypad on the dash look very last generation next to a C-Class Coupe, for example, while the central screen feels old-tech.

Practicality isn’t great, either – instead of proper door bins you get silly stretchy pockets, while the boot drops by over 100 litres when the folding metal roof is stowed. That roof will now fold on the move at least, as long as you remember to start the process before you move off, but it isn’t particularly quick to do so. 

Advertisement - Article continues below

Bigger changes are found under the bonnet. The SLC’s petrol range has embraced downsizing entirely – the massive V8 in the old AMG variant is now a twin-turbo V6, for example. Here, the SLC 300 model effectively replaces the old 3.5-litre V6 of the SLK 350, instead using a 2.0-litre turbocharged four-pot offering similar performance but better economy. It’s 60bhp down on the old SLK, but has the same torque figure and is lighter. That, combined with Merc’s slickest new nine-speed autobox, means the SLC completes the 0-62mph sprint just two-tenths slower than before in 5.8 seconds.    

It’s a punchy and flexible engine, revving keenly until it tails off near the redline, and the rapid fire gearchanges help you make the most of the strong mid-range, whether you take control via the wheel-mounted paddles or leave it to its own devices. 

Skip advert
Advertisement
Skip advert
Advertisement - Article continues below

Our car had the optional sports exhaust system, which emits a slightly uninspiring drone at low revs but gets more vocal when you rev it. It’s nowhere near as tuneful as the old V6 though, despite sounding good for a four-cylinder. It’s also impressively economical: a claimed combined figure of 47.1mpg is better than any Z4 and on a par with the slower 1.8-litre Audi TT. That should be enough to draw quite a few buyers away from the diesel.

Unfortunately, the rest of the driving experience doesn’t quite live up to the promise. Mercedes has retuned the springs and dampers to improve body control and ride quality, but you wouldn’t know it. Mid corner bumps jolt and crash through the frame, which unsettles the otherwise composed ride, especially around town.

That’s a shame, because grip levels are strong, while the SLC feels agile in any of its five Driver Select modes. Select Sport, or the almost too firm Sport +,  and the steering weights up, the air suspension tenses and the gearbox is quicker to react. However, the steering feels numb, too light and vague so dilutes the cars sporty feel.

Also, at nearly £40k before options, the SLC isn’t all that cheap, especially considering a Porsche 718 Boxster or Audi TT S Roadster can be had for a fraction more. It’s well-equipped and solidly built, but it just can’t compete with those two in terms of driver appeal.

Skip advert
Advertisement

New & used car deals

Vauxhall Corsa

Vauxhall Corsa

RRP £19,690Avg. savings £5,321 off RRP*Used from £11,399
Kia Sportage

Kia Sportage

RRP £28,065Avg. savings £3,066 off RRP*Used from £13,300
MG MG4

MG MG4

RRP £27,005Avg. savings £10,288 off RRP*Used from £10,490
Skoda Kodiaq

Skoda Kodiaq

RRP £39,025Avg. savings £3,224 off RRP*Used from £12,125
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

EU 2035 petrol and diesel car ban to be scrapped – will the UK follow?
Electric car charging mega test - charging overhead

EU 2035 petrol and diesel car ban to be scrapped – will the UK follow?

The head of the biggest EU party has told the press that from 2035, car manufacturers must reduce CO2 emissions by 90 per cent
News
15 Dec 2025
Inside Ford’s big comeback plan: Fiesta, small SUV, hybrid and VW relationship all explained
Ford Bronco Sport 2025

Inside Ford’s big comeback plan: Fiesta, small SUV, hybrid and VW relationship all explained

Exclusive analysis reveals Ford’s comeback plan: new Fiesta EV, hybrid crossover and working with Renault and VW
Features
11 Dec 2025
Car Deal of the Day: brand new Nissan Micra arrives with a bang at only £204 a month
Nissan Micra - front cornering, higher angle

Car Deal of the Day: brand new Nissan Micra arrives with a bang at only £204 a month

Before we’ve even had a chance to drive it in the UK, the all-new Nissan Micra is our Deal of the Day for 13 December
News
13 Dec 2025