Ten Second Review
Mercedes don't tinker with the SL too often and the launch of an all-new car is something of an event. Future-proofing a car in such a fast-moving development environment will prove tough but there can be few complaints as to the engineering on show, especially in the V8-powered SL500 model that many will want.
As successful as the last version of the Mercedes-Benz SL was, it was key to remember that this was merely an artful disguise of a fifth generation model that was launched way back in 2001. Over ten years is a marathon innings in a time of short attention spans and rapidly advancing technology, but right up to the end, the SL retained its appeal.
The 2012 Detroit Motor Show saw the unveiling the all-new SL and, if you had been following the thread of contemporary Mercedes design, the look will have come as no great surprise to you. Think upscaled SLK with a few more elements of SLS supercar thrown into the mix and you won't be far from the mark. It's fair to say that the shape has divided initial opinion but I have the suspicion that like much of this company's output, the lines will mature nicely. As for engines, well the entry-level SL350 has a 3.5-litre V6 borrowed from humbler Mercedes models, whilst the tuned top-of-the-range AMG models require lottery-winning money. That leaves the car we tried and the one tested here, the 435bhp biturbo V8-powered SL500.
It would be tempting to think that a car in this class doesn't have to be that good to drive; that it just needs a powerful engine and a modicum of refinement. This is Mercedes though and the depth of engineering verges on the neurotic. For instance, the steering knuckles and spring links on the front axle are also made out of aluminium to reduce the unsprung masses. The same also applies to virtually all the wheel location components on the rear axle. It doesn't stop there. The SL is offered with either semi-active adjustable damping as standard or there's an optional active suspension system ABC (Active Body Control) available as an alternative. Both suspension setups are teamed with an efficient electromechanical Direct-Steer system.
Engines? Tick that box. The new 4.7-litre V8 in the SL500 we tried develops 435bhp, up around 12 per cent on its predecessor while offering 22 per cent better economy. It's significantly faster than the old SL500 as well, carving almost a second off that car's sprint to 60mph, in this instance stopping the watch at just 4.6 seconds.
Dynamically, this car has always sat rather uneasily somewhere between a Porsche 911 Cabriolet and a BMW 6 Series, not as sharp as the 911, not as luxurious as the Six. With this sixth generation SL, the difference is fundamental. In this, thanks to lighter weight, a wider track and the clever semi-active adaptive damping, we no longer have a car that's neither one thing or the other but one instead, arguably able to offer much of the best of both worlds.
Design and Build
The biggest bang for their buck that car manufacturers can get is by taking unnecessary weight out of cars and old-school two-seat roadsters have often been notoriously lardy. The SL had grown a bit like that, which was a shame as the original model of 1952 featured a featherlight lightweight tubular frame. This time round, Mercedes has put the SL on a weight loss plan with its first all-aluminium bodyshell in a series-production model. Only very few components consist of other materials. The designers use the even lighter magnesium for the cover behind the tank. High-strength steel tubing is integrated in the A-pillars for safety reasons. The new aluminium bodyshell weighs around 110 kilograms less than it would using the steel technology from the predecessor.
Compared with its predecessor, the new generation of the SL is much longer 4612 mm (+50 mm) and wider 1877 mm (+57 mm), providing more room for more comfort in the interior, too. Shoulder room (+37 mm) and elbow room (+28 mm) have been increased, exceeding the dimensions normally found in this vehicle class. The folding Vario roof now operates in only 20 seconds and features three different versions: painted, glass or with the unique panoramic Magic Sky Control. The transparent roof switches to light to darkened glass at the push of a button. The car's styling? You'll need to be the judge on that one. We registered a 60:40 split in favour in this office.
Market and Model
You're looking at around £86,000 to own an SL500, a premium of around £11,000 over the entry-level SL350. As for rivals, well, a Jaguar XKR Convertible would save you a few thousand but cost you at the pumps. And a BMW 650i would cost £10,000 less to buy - but is also, I'd say, more than £10,000 less desirable. SL500 buyers also might be looking at a Maserati GranCabrio 4.7 V8 - but that requires a £100,000 budget.
What you're paying for here of course is advanced hi-tech cleverness, two examples of which debut on this SL. Let's start with 'Magic Vision Control', billed as an intelligent and efficient wipe/wash system. The washer fluid jets out of the wiper blade directly in front of the blade lip, in both directions of wipe. As a result, no water is splashed onto the windscreen during spraying to disrupt the driver's visibility, and you'll never fire it onto your passenger when the roof is down. You can even specify a heated wiper blade to prevents snow or ice forming on it in winter.
The other feature that speaks volumes of Mercedes' lateral thinking was the Frontbass system which utilises the free spaces in the aluminium structures in front of the footwell as resonance spaces for the bass speakers. This gives the SL's stereo a punch while freeing up space in the doors and saving weight. Clever.
Cost of Ownership
Mercedes SL buyers tend not to sweat the details of running costs too much, but for what it's worth, the fuel economy of the latest range has improved. This SL500, for example, returns 30.7 mpg on the combined cycle and a CO2 figure of 214g/km, making it considerably cleaner and more economical than its predecessor. That's thanks to the benefits conferred by an adjustable radiator shutter, an eco-gearshift programme for the 7G-TRONIC transmission, intelligent alternator management and a start-stop system that cuts the engine when you don't need it, stuck in traffic or waiting at the lights.
This being a new model in a line that tends to go beyond the normal vehicle design life cycles, it's fair to say that depreciation will be better than the class average. That's not saying too much when rivals such as the BMW 6 Series convertible and Aston Martin Vantage Volante both suffer quite harsh residuals, but it is offset by the fact that SL owners tend to offset depreciation somewhat by owning their vehicles for longer than average and thus also enjoy the benefits of the less vertiginous section of the car's depreciation curve.
Those traditionally sold on the charms on a Mercedes SL will certainly be sold on this SL500. They'll certainly like the look of it thanks to the lithe proportions and deft detailing. Removing weight from the chassis, as Mercedes have here, is absolutely the right thing to do, as is concentrating on improving efficiency under the bonnet.
Like its predecessors, the sixth generation SL offers a unique, fascinating and in some ways contradictory interpretation of sportscar motoring. It's not really suited to a track, yet it's more than just a very grand GT, a combination that won't suit if your preferences lie at either of these extremes. For many though, this will be the perfect way to reward themselves for a lifetime's endeavour.