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

I-PACE

2024 Jaguar

I-PACE

15,993 milesAutomaticElectric

Cash £36,350
View I-PACE
Korando

2021 SsangYong

Korando

15,257 milesAutomaticPetrol1.5L

Cash £17,799
View Korando
Puma ST

2023 Ford

Puma ST

24,476 milesManualPetrol1.5L

Cash £19,349
View Puma ST
C-HR

2017 Toyota

C-HR

38,538 milesManualPetrol1.2L

Cash £13,199
View C-HR

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

Vauxhall Corsa

Vauxhall Corsa

RRP £19,690Avg. savings £5,988 off RRP*Used from £10,549
Nissan Juke

Nissan Juke

RRP £19,785Avg. savings £4,644 off RRP*Used from £9,562
Audi A3

Audi A3

RRP £26,295Avg. savings £2,713 off RRP*Used from £10,970
Skoda Kodiaq

Skoda Kodiaq

RRP £39,025Avg. savings £3,528 off RRP*Used from £9,444
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

All-new Dacia Striker is a cut-price Golf rival with an estate shape
Dacia C-Neo - exclusive image front

All-new Dacia Striker is a cut-price Golf rival with an estate shape

The Dacia Striker, formerly known as C-Neo, will be revealed in full on March 10th with a more conventional hatch version to follow
News
5 Mar 2026
Jaecoo 7 recalled: a quarter of all brand’s 2025 UK cars going back to dealers
Jaecoo 7 - front action

Jaecoo 7 recalled: a quarter of all brand’s 2025 UK cars going back to dealers

The Chinese brand has initiated a recall for roughly 7,500 Jaecoo 7 models due to an incorrectly attached wiring harness clip
News
6 Mar 2026
Why EVs are so expensive to insure, and how to make them cheaper
Ford Puma Gen-E - front action

Why EVs are so expensive to insure, and how to make them cheaper

Research shows that EVs are usually 15 to 25 per cent more expensive to insure than petrol cars – the experts at Thatcham say they have the solution
News
3 Mar 2026