Mercedes-AMG 2015 SLK55 vs 2017 SLC43

Mercedes-Benz SLC News

Staff Member

To upgrade, or not to upgrade? That is the question.

When a new model of the car you own is released, it's only natural to look at what has changed to see if the update is worth the time, effort, and most importantly, cost.

Major generational updates sometimes make the decision quite easy to rationalise, but when the changes are concentrated on just a couple of components, is the argument weighty enough?

Take the pint-sized Mercedes-Benz SLK roadster for example.

The diminutive sportster celebrates its 20th anniversary this year, and for a long time was the most cost-effective way into a topless Benz.

When the third-generation R172 SLK landed in 2012, the range peaked with the SLK55, packing a 310kW/540Nm 5.5-litre naturally aspirated V8 under its sloping bonnet.

The SLK55 continued to lead the charge until 2015, when the range was given a mild update.

I say mild, as it was from a technical perspective, but it was significant from a model point of view.

Part of a restructure of Mercedes-Benz and Mercedes-AMG vehicle nomenclature saw the SLK name dropped in favour of the more family-connected, and historically relevant, SLC.

Again, an AMG variant tops the five-model range, but the familiar 55 has gone, replaced by an SLC43.

The eight has become a six.

As we learned when speaking with Mercedes-AMG boss, Tobais Moers, at the Geneva motor show last year, the once sensible model numbers that identified engine capacities, are now more to signify a level of performance.

But what does that mean for the little roadster now that the range topper has dropped 12 AMG points? Let's take a closer look...

When it was launched, the R172 SLK55 carried a $155,000 (all prices are noted before options and on-road costs) price tag. This increased over its four years in market to a final of $162,010 for the 2015 Mercedes-Benz SLK55 AMG.

The 2017 Mercedes-AMG SLC43 comes in a solid $27,395 lower, at $134,615. That's a 17 per cent saving, or about $2300 per AMG point on the back.

Both cars came highly specified, with 18-inch alloy wheels, AMG body styling packages and Nappa leather upholstery. But the K-to-C update sees more equipment thrown at the newer car, beyond what would be expected of a facelift.

So yes, new headlamps that feature adaptive LED technology replace the bi-xenon units on the older car, and the glass panoramic roof, which was a $1750 option on the SLK is now standard equipment.

Inside, there are minor changes to the centre console to cater for the new gearbox, the SLC moving away from the seven-speed AMG Speedshift automatic to the new nine speed 9G-Tronic.

The SLK makes up for the glass roof option here, having dual-zone climate control as standard, where it is a $1475 option in the SLC.

Strangely though, the SLK doesn't have a rear-view camera, something which has been rectified on the newer car.

There's a new grille on the SLC, featuring the now familiar diamond-style pattern, and an updated rear valance. But to the casual observer, the cars are still very hard to tell apart.

In a way the '55 still looks more muscular and angular, as the lines on the SLC have been softened somewhat. The four oval-tipped exhausts on the V8, and cleaner bumper lines also work a bit better than the angular exhaust assembly and flared vents on the '43.

The core shape remains the same, with identical width (1810mm), height (1301mm) and wheelbase (2430mm), but the SLC is 13mm shorter (4146mm vs 4133mm) thanks to the stubbier nose.

As a model, the roadster does look better with the roof down, the clever three-piece folding hard top carried over in functionality and speed of deployment. It's still slow, however.

The 17 colours available on the SLK55 have been trimmed to just 12 options on the SLC43. It makes sense, the choice of four different blacks seemed excessive, with just Hyacinth Red and Brilliant Blue now breaking up the ?Melbourne palette' of black, white, silver and grey.

Inside, there is a new steering wheel design, and some minor changes to the fascia trim; gloss is now matte, dark carbon-fibre textures now light, but the overall feel of the cabin is nearly identical.

Even the seven-inch recessed screen is the same.

Like many current-generation Mercedes models, despite its name change, the SLC is still a five-year old model and shows it more than most.

The biggest change then, is under the bonnet.

We all loved the concept of the SLK55, a lightweight (1555kg tare) two-seater with an enormous engine under the bonnet.

The 5.5-litre V8 was very much an AMG engine, adhering to the one-man one-engine build philosophy.

Power is a solid 310kW which comes on high in the rev range at 6800rpm, with peak torque of 540Nm offered from 4500rpm. This is good for a power-to-weight ratio of just under 200W/kg (199.4).

The SLC43 is part of a new generation of AMG cars. Engineering and development is done with involvement of the team from Afalterbach, but the cars, and more importantly, the engines, are built alongside ?regular' Mercedes-Benz models.

The 3.0-litre twin-turbo V6 has slightly tamer numbers than the V8, with 270kW available from 6000rpm and 520Nm of torque from just 2000rpm. The car actually weighs 36kg more than the '55 (1591kg tare) and as such has a lower power-to-weight ratio of 169.7W/kg.

So that's a done deal then? All hail king '55? Not quite.

Moving from a naturally aspirated motor to a twin-turbo unit has changed the drivability of the little roadster.

Mercedes claims just a tenth of a second favour to the V8 in the 0-100km/h sprint (4.6 to 4.7 seconds), but during our tests we managed to get a better launch from the V6 and switched the numbers around, albeit just off the claimed pace for both cars (5.0 in the SLK and 4.9 to SLC).

But the difference is not really felt when nailing the car in a straight line, but driving it with a modulating throttle.

Where the V8 gives a nice little growl and the aural sensation of a funnel of air breathing through the car, the V6 is a big, brash, brass band. It's a sweet, sweet note that, thanks to the more accessible torque lower in the rev range, is a more easily played tune.

Yes, the V8 can sound quite raucous at the redline, but you need to be moving with purpose to get the most out of it. The V6 is much more idiot proof in satisfying that performance demand.

Put simply, the SLC is punchier than the SLK. You feel like the car has more power and greater performance because you can use it. Seat of the pants beats numbers every day.

It's not as thirsty either, with a claim of 7.9L/100km against the 8.5L/100km in the V8. We ah, didn't get very close to these in either car, but the average consumption on the SLK was higher on the same drive loop, and that's what counts.

As noted earlier, the transmission has changed from the seven-speed AMG unit to the nine-speed Mercedes one. It is smoother, particularly on take off, but nine-ratios seems a bit silly, especially if you are shifting manually.

Even cruising on the freeway, both cars would settle into fifth or sixth quite happily, so to think that in the SLC you still had seventh, eighth and ninth to go seems a little pointless.

There is no adaptive suspension in either car, what you see is what you get, and it has been tuned for that middle of the road ability where its comfortable enough for cruising but will let you know when the road gets choppy, and direct enough to give decent performance feedback but not quite firm enough to monster through a winding, country road.

Mix the two on one direction, on some smooth, flowing sweepers and both little Mercedes are delightfully entertaining. Go the other way, at pace through some poorly surfaced corners, and confidence all but evaporates.

The SLC, like the SLK is more of a boulevard runner than an open-top sports machine. The AMG variants simply turning the drama up to 11, while maintaining the car's PG timeslot.

It's a little bit sad to see the SLK55's V8 fall by the wayside, but in terms of enjoyment and drivability the twin-turbo V6 is a suitable replacement, even if not when looking at the numbers on paper.

Mix that with the $30k saving and the SLC43 is a worthy successor.

Is it reason enough to upgrade, though?

Honestly, if you have an earlier R172 AMG in the garage, the changes just aren't expansive enough to really warrant a move. The SLK55 is still a fun and special car, where the '55 on the back still means a '55 up front.

If you are contemplating the purchase of the little Mercedes roadster though, and aren't sure whether a late-run SLK will suit more than a shiny, new SLC, that usable powerband and wonderful noise made by the V6 is reason enough to go for the newer car.

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