Used Mercedes SL 2012-2020 review

Buying used car, as we all know, is a truly excellent way of recycling, but a used Mercedes SL provides the best way of recycling smugness. The first owner would have felt invincible for being able to afford to drive such a vast and luxurious car. However, second-hand buyers can experience a similar warm glow; buying used enables them to enjoy that same imperious driving experience for less than the price of an entry-level Ford Focus.

When the SL appeared in 2012, it could be had with either a 302bhp 3.5-litre V6, badged SL 350, or a 435bhp 4.7-litre turbocharged V8, labelled SL 500. Later on, the SL 350 became the SL 400 and got a smaller yet more powerful 328bhp, turbo 3.0-litre V6. Top of the tree were the AMG models, starting with the 577bhp SL 63 with a 5.5-litre V8 and leading to the very rare 621bhp 6.0-litre V12 SL 65.

Initially, there weren't any trim levels per se, but all SLs came with 18in alloys, heated leather seats, sat nav, DAB radio, dual-zone climate and rear parking sensors. There were many options and packages available, though, including a driver assistance pack with lane-keeping assist, blind spot monitoring, automatic emergency braking and adaptive cruise control; a luxury (renamed premium) pack with a rear view camera, cooled seat with a massaging function, and upgraded Harmon Kardon stereo, keyless entry and start, plus soft-close doors. It seems amazing buyers even had to pay extra to have a memory function for the driver's seat, mirrors and steering wheel position, as well as for power-folding mirrors.

We saw the introduction of AMG line after the 2016 facelift, to fit in with the trim naming structure of other Mercedes models. This also introduced the Night package that brought in bigger 19in (20in on SL 63) alloy wheels and lashings of gloss black exterior trim. Further revisions in 2019 brought in Grand Edition and Grand Edition premium, the latter of which includes the premium pack.

You might be surprised to find that the SL is fairly agile for something with such vast exterior dimensions. This is because a lot of attention was paid to reducing weight over the previous generation SL; the car is made mostly from aluminium and the folding roof is magnesium in order to keep it below two tonnes, even when loaded with optional extras.

However, the SL is still no sports car. Numb steering that doesn't provide any real sense of the grip levels, a slightly mushy brake pedal and an automatic gearbox that refuses to provide quick downchanges all discourage you from pushing this car beyond a respectable canter. You can tell that's what it's happiest doing because you'll experience very little buffeting with the roof down and the windows and wind deflector up. Even at motorway speeds. If you're looking for driving thrills along with the wind in your hair, buy a Porsche 911 convertible instead.

This Mercedes is better suited to grand touring, which is why its interior is so nicely finished, with supple leather across almost every surface along with classy satin chrome finishes for the air vents and various knobs and switches. The seats and steering wheel adjust in a multitude of ways (particularly examples equipped with the multi-contour seats that come with the luxury/premium pack) so occupants of all shapes and sizes can get comfortable. There's even a decent view out because you sit higher than you would in most sports cars.

Having said all of that, there isn't quite as much luggage space as you might expect given how big the SL is. On paper, the SL has more luggage capacity in litres than the BMW 6 Series convertible, but due to the bulky folding metal roof, the SL's boot itself is rather shallow and will struggle to accommodate suitcases. You're better off packing squashable bags instead and utilising the many hidden storage areas dotted around the interior – particularly the two behind the seats – for smaller items.

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Remarkably, you can buy this once £70,000+ car for around £20,000, and because these are often "high days and holidays" cars, even early 2012 examples won't have huge mileages. Most will be the smaller engine SL 350, with the less popular SL 500 carrying a premium and most examples sitting at around the £25,000 mark. A facelifted 2016 SL starts from £30,000 for an SL 400 with the revised engine. Expect to pay nearer to £35,000 for a pre-facelift SL 63, and more like £60,000 or more for the post-facelift version.

A year-old example with minimal mileage form a Mercedes dealer can be found a few grand less than £70,000, which is a useful saving over what one cost new.

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MPG

Sticking with the base engines means you should have to stop less for fuel. The most economical is the SL 350, with a combined figure of 37.7mpg, followed by the SL 400 at 36.7mpg. Then there's the SL 500 at 30.7mpg, but the SL 63 and SL 65 are by far the worst at 28.5mpg and 24.4mpg, respectively. These two most definitely needed to have been ordered with the enlarged 75-litre fuel tank.

CO2 emissions

The SL certainly isn't going to win any climate change awards because even the best engine (SL 350) emits 176g/km, with the SL 400 upping that marginally to 178g/km. Go for either of the two V8s and that figure gets bumped up to 214g/km for the SL 500 and 234g/km for the SL 63. Both pale in comparison to V12 SL 65 with an output of 270g/km.

Car tax

Car tax for all models registered before 1 April 2017 will vary depending upon the emissions the engine produces (see paragraph above for more information) while examples registered after this date will render owners liable to pay a flat rate fee of £155 per year (which applies to all petrol and diesel cars), plus an additional fee, currently £335 per year for years two to five, because every version of the SL cost more than £40,000 when new. Fortunately, this yearly additional fee only lasts between the second and sixth years of the vehicle's age, then it goes back to the flat rate fee. To find out more about the current road tax costs, click here for further information.

Servicing costs

Looking after you SL at a main dealer will not be cheap because even opting for fixed-price servicing will see you forking out over a £1000 for pre-booking the following two services.

Engine

There shouldn't be any need to look beyond the entry-level 350 or revised 400 models because these provide decent performance without excessive fuel consumption to ruin your cruising range.

Specification

There aren't really any differences in trim because every SL comes loaded with kit. There are optional packages to watch out for, but the standard car is more than well-appointed enough for plebs like us.

Our favourite Mercedes SL: SL 350 or SL 400

The last of the Jaguar XKs could be seen as a sportier alternative to the SL thanks to its bombastic V8 and lightweight construction. You will have to offset that against the fact that the Jaguar is the far older design, so it won't have the same wow factor when it comes to technology or infotainment.

If you really did want a sports convertible then look no further than the Porsche 911. Unlike the SL, the 911 does actually come with two rear seats with proper belts, but don't expect anyone to be able to sit there without you scooting forward slightly. Best to think of those chairs as a place to supplement the small boot that can be found in the nose of the car. Aside from that, the 911 will leave an SL for dead on a challenging B road.

The BMW 6 Series convertible is a more practical alternative because it comes with four seats and can be had with a very economical diesel engine. The interior is very well finished, too, so it won't feel too much of a downgrade compared with the SL.

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