Independent, Expert EV Reviews & Advice Since 2006

Mercedes-Benz SLK 250 CDI Review

30 March 2012 by Paul Clarke
Mercedes-Benz SLK 250 CDI

Mercedes-Benz SLK 250 CDI


Mercedes-Benz SLK 250 CDI Road Test

Eco Facts

Model/Engine size:
BlueEFFICIENCY AMG Sport Edition 125

Fuel: Diesel

Fuel economy combined: 56.5 mpg
Green-Car-Guide rating: 8/10
The Mercedes-Benz SLK is an icon, and for the first time, you can now have this icon with a diesel engine, resulting in fuel economy of 56.5 mpg .

The phrases Mercedes-Benz SLK and 56.5 mpg Ц together with 132 g/km CO 2 emissions – have never previously been heard in the same sentence. But nowthis SLK offers a combination of efficiency and a hugely aspirational image in a luxurious two-seater convertible.

Mercedes-Benz SLK 250 CDI Rear View  Mercedes-Benz SLK 250 CDI Design

Although it may look Сsporty’, this isn’t an out-and-out sports car; it majors more on image than excitement. But most owners won’t be worried about this Ц they’ll be more concerned about arriving in style and comfort . And the SLK is a master at providing that feel-good sensation. If you want to push on along winding B-roads, then the SLK is very capable in a stable and surefooted way; it’s just that there are more sporty two-seaters out there, which is fine, as the SLK has its own niche in the market.

The looks of the SLK have recently been updated. Previous versions were rather rounded and not particularly dynamic-looking. Now it has a more aggressive front end , and side and rear profiles that share certain design cues with its much bigger, faster and more expensive stablemate, the SL.

Inside, the SLK gives an impression of luxury; the materials and controls feel high quality and there’s all the equipment that you’d want. The COMAND multimedia system, and especially the satnav, may not be the easiest to enter information into, but once it’s working it’s impressive, even giving you temporary speed limit notifications on motorways. The SLK also tells you if you’re too close to the car in front.

It may be a relatively trivial thing, but we’re not big fans of the indicator/windscreen wiper stalk being positioned so close to the cruise control stalk; it’s too easy to intend to indicate but to instead set the cruise control by mistake. At rest, the indicator stalk also doesn’t sit level, instead it’s slightly lower; this means you’re not always sure whether the indicator is on or off.

The Сvario-roof’

Mercedes-Benz SLK vario roof Mercedes-Benz SLK Vario Roof

The quality feel also extends to the С vario-roof ’, which, at the touch of a switch, folds from a solid metal and glass structure into individual pieces which are stowed away in the boot, leaving an open-top car. The car looks good with the roof down, but it also looks good with it up. We also think that the SLK looks better from the rear than from the front, as the rear is a somewhat cleaner design.

Even with the roof down, the boot remains useable. Before lowering the roof you need to pull out a partition in the boot , and any luggage needs to go underneath this. The roof stows away above this panel, and there is still reasonable room below it in the boot, although the access is reduced.

Mercedes-Benz SLK 250 CDI driving experience

The Mercedes SLK 7-speed automatic gearbox In terms of the driving experience, the SLK doesn’t initially feel as though it has sharp or sporty responses through the accelerator pedal. However at higher speeds, getting past slow traffic is easy thanks to strong acceleration from the powerful and torquey 2.2-litre turbodiesel.

The SLK comes with a 7-speed automatic gearbox which matches the accelerator in terms of responses that aren’t instantaneous, especially in its default Economy mode. There’s a small button to right of the gear selector which allows you to toggle from Economy setting to Sport and then to Manual.

Selecting Sport means that the Сbox keeps the car in higher revs for longer , giving better responses. But for best control on B-roads it’s preferable to use the transmission in manual, operating the paddles on the steering wheel to hold the car in the gear that you want. Of course in reality the car is likely to be driven in auto mode for the vast majority of the time. Although it has automatic transmission, the SLK has a stop/start system, which proved to work very effectively.

The SLK’s steering is well-weighted and has an appropriate feel for the car, but it’s not the most precise of systems. Likewise, the car’s chassis and suspension is designed more for comfort than agility. However the SLK is a relatively small car and small cars always feel good to drive, especially if they have a well-engineered chassis and sufficient power.

There’s some wind (and road) noise with the roof up, especially at motorway speeds, and some buffeting with the roof down. There’s no noticeable Сscuttle shake’ associated with convertibles, and if you’re driving the SLK on a sunny but cold day, the car’s Сair scarf’ can direct warm air around your neck. mercedes-slk-007.jpg

So thanks to its secure rather than sporty handling, the SLK may be more suited to cruising around towns than driving enthusiastically through the countryside . However it also proved to be an extremely efficient car on motorways .

Over a 60-mile stretch of motorway the SLK averaged 61.4 mpg. That’s one of the best economy results that we’ve recorded , and it beats most petrol superminis that we test under similar conditions by a long margin. During our week and 1000 miles with the car, overall we achieved 51.3 mpg.

The SLK also feels incredibly planted to the road at motorway speeds. And even with the 18-inch AMG alloy wheels, low profile tyres and sports suspension of our test car, the ride was still mostly comfortable, except over some poor surfaces and urban potholes.

The main issue is that most people will assume this is a sports convertible, but it doesn’t have sports car dynamics, whereas other rivals do offer more entertainment in the handling department.

Of course this SLK is a diesel and you can tell this from the noise, especially from outside, although it’s generally refined inside.

Other than that, we just need to remember that this should be a good car, as it’s not cheap. Our test car cost £36,250. It does come with decent levels of standard equipment including cruise control, variable speed limiter, air conditioning, AMG bodystyling, sports seats, sports steering wheel, and sports suspension. There’s also lots of standard safety features, such as Attention Assist, which monitors steering behaviour and alerts you if it thinks you’re tired.

However our test car also had a number of options including COMAND online system with media interface (£1995), Distronic Plus (£1495), memory package for front seats and exterior door mirrors (£1030), and intelligent light system (£895); all the options took the total price of the car to £47,605. That’s quite a lot for a small two-seater sports car that isn’t really a sports car.

If you like the sound of the SLK but don’t want a diesel, there are four petrol engine options; two turbocharged 1.8-litres, a 3.5 V6 and a 5.5 V8; predictably these engines don’t come anywhere near matching the fuel economy of the diesel.

Mercedes-Benz SLK Vario Roof Summary

For people looking for high levels of economy in a convertible, they’ll no doubt be pleased that the Mercedes-Benz SLK 250 CDI can now combine luxury open-top motoring with 56.5 mpg .

Diesel engines are now sufficiently advanced to offer performance and refinement, and this engine is not out of place in this car. Most people take notice of the SLK; they take even more notice when they find out that it manage these levels of economy.

For combining a car with such an iconic image with 56.5 mpg, the Mercedes-Benz SLK gets a Green-Car-Guide rating of 8 out of 10 . For some, the fact that it doesn’t have sports car dynamics will be an issue; however if you’re looking for a two-seater convertible that majors more on luxury rather than sportiness, whilst also combining efficiency, then the SLK 250 CDI could be the answer.

Car Facts and Figures

Mercedes-Benz SLK 250 CDI:

Fuel economy extra urban: 65.7 mpg

Fuel economy urban :45.6 mpg

132 g/km

Green rating: VED band E – First year £115

Weight: 1590 Kg

Company car tax liability (2011/12): 19%

Price: £36,250

Insurance group: 20

Power: 204 hp

Max speed: 151 mph

0-62 mph: 6.7 seconds

DPF: Yes

More images:

mercedes-slk-012.jpg mercedes-slk-008.jpg



Paul Clarke


More car reviews >>

Read our Mercedes-Benz E220 CDI BlueEFFICIENCY review

Read our Audi TT TDI review

Read our BMW 640d review