Skip advert
Advertisement

Mercedes SLK 55 AMG

Latest AMG flier adds V8 muscle to coupe-cabrio package

It’s fair to say that in the eyes of keen drivers, the Mercedes SLK has always lived in the shadow of the Porsche Boxster. But bring the brand’s famous AMG tuning division into the equation, and things aren’t as clear cut.

The SLK 55 AMG is powered by a 5.5-litre V8 engine, and its mighty 415bhp power output goes some way to justifying the car’s hefty £54,965 price tag.

Advertisement - Article continues below

It’s just a shame the uninspiring styling doesn’t do the same. Parked next to the Porsche, the SLK looks bulky – partly because accommodating the two-section metal roof gives it a heavy rear end.

The top takes a lengthy 20 seconds to fold, and doing so reduces boot volume by 110 litres, to 225 litres. Plus, refinement with the roof in place is no better than in the fabric-hooded Audi and Porsche.

The cabin offers decent space, and there’s plenty of adjustment on the seat and steering wheel. The deep-set dials and turbine-style air vents are nice touches, while navigation, Bluetooth, DAB radio and heated seats are standard.

Our car also featured the £395 Airscarf system, which blows warm air around your neck. It had a pair of optional pivoting transparent air deflectors, too, but we still found the cabin blustery.

Skip advert
Advertisement
Skip advert
Advertisement - Article continues below

Used - available now

Model Y Premium

2023 Tesla

Model Y Premium

25,335 milesAutomaticElectric

Cash £26,697
View Model Y Premium
Aygo

2019 Toyota

Aygo

40,666 milesManualPetrol1.0L

Cash £8,697
View Aygo
Tucson

2023 Hyundai

Tucson

22,248 milesAutomaticPetrol1.6L

Cash £18,997
View Tucson

The ride isn’t as composed as the Porsche’s, either, and with some creaking around the screen the body doesn’t feel as rigid – although at low speeds the suspension isn’t as bone-jarringly stiff as the TT’s.

Still, on flowing roads the SLK feels heavy compared to the Boxster and the steering lacks the Porsche’s razor-sharp precision.

There’s more weight transfer as you turn into a bend and on the exit of corners the stability control works hard to maintain traction. Overall, the Merc isn’t as engaging as the Porsche and doesn’t offer the surefooted traction and body control of the Audi.

It has one trump card, though: the 5.5-litre engine. It’s claimed to be the world’s most fuel-efficient V8 and uses Formula One-inspired technology to shut off four of the cylinders at low speeds. The end result is CO2 emissions of just 195g/km, plus during our test we averaged an impressive 30.3mpg.

But AMG’s focus on efficiency hasn’t diluted the car’s performance. With 540Nm of torque, there’s a wave of effortless mid-range acceleration, and the seven-speed DCT transmission changes gears smoothly and quickly. You get a firecracker exhaust note and a lovely throttle blip on downshifts, too.

So while it’s difficult to ignore the Porsche’s greater driver engagement, the SLK’s blend of performance and efficiency stands it in good stead.

Details

Chart position: 2Why? The SLK 55 is pricey, but you get a folding hard-top, plus clever V8 combines highest power output with strong efficiency.

Skip advert
Advertisement

New & used car deals

Skoda Kodiaq

Skoda Kodiaq

RRP £39,045Avg. savings £3,528 off RRP*Used from £8,970
Omoda 5

Omoda 5

RRP £24,040Avg. savings £1,535 off RRP*
MG MG4

MG MG4

RRP £27,005Avg. savings £6,250 off RRP*Used from £8,672
Volkswagen Polo

Volkswagen Polo

RRP £15,270Avg. savings £1,925 off RRP*Used from £6,777
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

New cars cost too much but some brands are finally finding the price sweet spot
Opinion - new car prices, header image

New cars cost too much but some brands are finally finding the price sweet spot

New cars are expensive, but Mike Rutherford is pleased to see that some manufacturers have found a pricing sweet spot
Opinion
12 Apr 2026
We got it wrong: VW ID.3 and ID.4 will be replaced by “true Volkswagens”
Volkswagen ID.3 - front and rear

We got it wrong: VW ID.3 and ID.4 will be replaced by “true Volkswagens”

The inside story on how the people’s car maker lost touch with the people, before rediscovering its mojo under boss Thomas Schäfer
News
10 Apr 2026
New Nissan Juke revealed with sharp origami-inspired design and EV power
New Nissan Juke unveiled in Japan - Auto Express editor-at-large Phil McNamara stood next to the car

New Nissan Juke revealed with sharp origami-inspired design and EV power

“No compromise” design for Leaf’s baby brother, which is bigger and more spacious than today’s combustion-engined Juke and goes on sale in a year
News
15 Apr 2026