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

M2

2020 BMW

M2

58,160 milesAutomaticPetrol3.0L

Cash £30,990
View M2
S-Max

2022 Ford

S-Max

51,163 milesAutomaticDiesel2.0L

Cash £19,960
View S-Max
T-Cross

2023 Volkswagen

T-Cross

15,304 milesAutomaticPetrol1.0L

Cash £15,890
View T-Cross
Focus Estate

2023 Ford

Focus Estate

30,273 milesManualPetrol1.0L

Cash £14,324
View Focus Estate

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

Omoda 5

Omoda 5

RRP £24,040Avg. savings £1,761 off RRP*Used from £15,700
MG MG4

MG MG4

RRP £11,180Avg. savings £4,250 off RRP*Used from £11,116
Skoda Kodiaq

Skoda Kodiaq

RRP £39,390Avg. savings £9,673 off RRP*Used from £24,750
Volkswagen Polo

Volkswagen Polo

RRP £8,495Avg. savings £2,298 off RRP*Used from £6,165
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

New BMW 3 Series 2026 review: too good for Audi and Mercedes
BMW 3 Series - front

New BMW 3 Series 2026 review: too good for Audi and Mercedes

The new BMW 3 Series is everything we hoped it would be, with superb driving dynamics and a premium feel throughout
Road tests
29 Oct 2026
New BMW i3 2026 review: drives just like an electric 3 Series should
BMW i3 - front

New BMW i3 2026 review: drives just like an electric 3 Series should

We get behind the wheel of the new BMW i3 to see if it's as good as it looks on paper
Road tests
30 Oct 2026
New Toyota hybrid engine on its way, and it could return over 85mpg
Next-gen Toyota hybrid engine

New Toyota hybrid engine on its way, and it could return over 85mpg

Japanese giant has put all of its engineering might behind new 1.5-litre engine, and is now teasing us with what to expect
News
28 Oct 2026