2012 Mercedes-Benz SLK350 First Drive

Republished: 03/07/2011  (Original Date: 03/08/2011)  - by Erin Riches, Senior Editor

Island vacations are usually not our thing, but while driving the redesigned 2012 Mercedes-Benz SLK350 around Tenerife, the largest of the Canary Islands, we have a change of heart.

Tenerife's coastline is jammed with mega beach resorts, most of them packed with German tourists. But hidden away from the tropical beaches we find Mount Teide, the third largest volcano in the world, and home to some really good driving roads.

Earlier Mercedes-Benz SLK-Class convertibles weren't known for their abilities on back roads, and we certainly wouldn't tell you that the third generation of Benz's baby hardtop convertible is some kind of Boxster substitute. However, the 2012 Mercedes-Benz SLK350 is capable in its own way, and we easily dodge the occasional tourist in a rental minicar.

More impressive than the 2012 Mercedes-Benz SLK350's hatchback avoidance capability, though, is its out-and-out refinement. It offers a level of ride compliance that eludes its main competition, plus a well-designed and versatile retractable hardtop.

Still Small and a Bit Sportier
An SLS-inspired nose identifies the latest incarnation of the Mercedes-Benz SLK-Class. It's enough to make the locals gawk, although it's hardly a radical departure from the previous design. Underneath its evolved bodywork there's a new chassis based on the latest W204 version of the C-Class platform architecture.

This is still a much smaller car than the C-Class sedan, as the 2012 SLK retains the outgoing model's 95.7-inch wheelbase. The SLK350's track grows barely an inch to 61.4 inches in front and 61.8 inches in back. It's also 1.2 inches longer from its snub nose to its shapelier tail and just over half an inch wider at 71.3 inches. The curb weight has edged up about 80 pounds.

The basic suspension design is the same as before, with struts and a couple lower links in front and a multilink rear. One improvement, says Dr. Rudiger Rütz, senior manager of driving dynamics, is a more direct-motion ratio for the 2012 SLK's slightly thicker rear stabilizer bar to help reduce body roll.

Mercedes engineers also increased both compression and rebound damping, and U.S. models will have our European-spec SLK350 tester's optional adaptive dampers as standard. Additionally, all U.S.-bound 2012 Mercedes-Benz SLKs will have a sport-tuned suspension calibration, while the standard European setup will be less aggressive and ride slightly higher. Eighteen-inch wheels are standard, and they'll be fitted with Continental ContiSportContact 5 tires measuring 225/40R18 front and 245/35R18 rear.

Adapts to Its Environment
The 2012 SLK convertible retains its predecessor's passive variable-ratio steering, which simply uses gear teeth that are variably spaced on the steering rack. The on-center ratio is 14.5:1, and it quickens by a total of 30 percent by the time you reach full lock. It works particularly well on Tenerife's tight mountain passes, tidying up our inputs in decreasing-radius turns.

The brake rotors are larger this year, with 13.5-inch discs up front and 11.8-inch discs in back (versus 13 and 11.4, respectively, in 2011). Pedal feel is excellent as we hammer around some tight winding roads.

A new cornering brake control system is new to the SLK-Class for 2012. We notice it working through those same tight corners as it brakes the inside rear wheel to bring our SLK350's nose around as we get back on the throttle. Of course, there's still a lot of weight up front, so if you start driving like you're not on vacation, you'll eventually get noticeable understeer.

Dr. Rütz tells us, "The optimal SLK for driving is the SLK250 with the 18-inch wheel/tire package." It may only have a 201-horsepower turbocharged and direct-injected 1.8-liter four-cylinder engine, but the SLK250 is nearly 100 pounds lighter, he notes. Unfortunately, it's the SLK we never got a chance to drive.

Better V6, Same Seven-Speed Automatic
It's OK, though, because with the adoption of direct injection, the 3.5-liter V6 is finally good enough to justify the SLK350's price tag. The horsepower gain is slight — 302 at 6,500 rpm versus 300 for 2011 — but the torque comes together earlier and lasts longer. Formerly, it peaked at 265 pound-feet at 4,900 rpm, and now you have 273 lb-ft from 3,500-5,250 rpm.

Although Mercedes isn't predicting any improvement in 0-60-mph acceleration (5.4 seconds is the claim), this V6 is more likable on an unquantifiable level. It sounds sweet and feels responsive as we merge onto Tenerife's coastal loop highway. With the ample midrange torque, we scarcely notice the lower redline, now 6,800 rpm instead of 7,200.

Mercedes engineers will make one key modification to the direct-injected V6 for the U.S. market: The European version uses stratified-charge combustion in low-load situations up to 3,800 rpm. Ours will not, and it'll be 10 percent less fuel-efficient as a result. Mercedes engineers tell us it's because of the higher sulfur content in U.S. gasoline, which would destroy the NOx catalyst on the stratified-charge V6.

A seven-speed automatic transmission drives the rear wheels of every 2012 Mercedes-Benz SLK350; if you're among the three people in America who desire a manual-shift SLK, wait for the SLK250. Gear ratios are unchanged on the SLK350's seven-speed, though the final drive is slightly taller at 3.07:1 versus 3.27 previously. Engineers have made various improvements to this transmission to reduce torque-converter slip and frictional losses.

Our Euro-spec test car's transmission has an additional electric oil pump to lubricate the clutches when the start-stop function engages in Eco mode. Start-stop is a nonintrusive affair in the SLK350, but it doesn't matter: No U.S.-bound SLK will have the start-stop feature.

Even so, our 2012 Mercedes-Benz SLK350 will consume less fuel than the 2011 model. Mercedes predicts a 20 city/29 highway mpg rating compared to 18/26 on the 2011 SLK350. On the flip side, the seven-speed will serve up some pretty aggressive downshifts in Sport mode, but will not rev-match them like the dual-clutch gearbox in the BMW Z4.

Magic Roof, Clement Cabin
Mercedes will offer three different roof options on the 2012 Mercedes-Benz SLK350 convertible. If you're straitlaced and frugal, there's the standard, all-metal retractable roof. There are two options on top of that: a sun-reflecting, panoramic glass roof, and what Mercedes calls its Magic Sky Control roof, which lets you create your own partial solar eclipse in the car.

Of course, it's not magic at all, but a real-life application of a plate capacitor: On the SLK, a bunch of crystals are suspended in fluid between two glass panels. When you apply a 120-watt charge to the unit, the crystals align and allow sunlight to pass through. Cut the electricity and the crystals disperse randomly, partially blocking the transmission of light and, on warm days, reducing air-conditioner load.

As the rain becomes a downpour, we raise the roof on our 2012 Mercedes-Benz SLK350 and immediately find ourselves talking to our passenger about absolutely nothing just to fill the uncomfortable silence — it's that quiet. We drop the roof again, even though it's barely 50 degrees, because between the AirScarf system (which we've determined is overkill if you've donned an analog scarf), the industrial seat heaters and the fixed-glass wind blocker, you can basically change your climate to suit.

Our car did not have the new Airguide pivoting wind-blocker panels, but if you have a magic roof and a simulated scarf, you might as well have the wind blocker do your bidding as well.

For a Car Guy's Day Off
The 2012 Mercedes-Benz SLK350 goes on sale in the U.S. this June priced within 2 percent of the 2011 model, we're told, and will be followed by the SLK250 in February 2012 (it replaces the SLK300) and, later in 2012, the SLK55 AMG (nope, not the SLK63).

So we'll have to wait awhile for the V8 version, but for now this new SLK handles better than its predecessor, accelerates with more fervor and offers yet more of the cutting-edge amenities that made it the original 365-day convertible. No, the SLK350 isn't the most engaging two-seat convertible in the world, but it's one of the most comfortable. It's not quite a full GT, yet it's certainly more than a minimalist roadster.

That might sound like faint praise, but this is a niche vehicle. Mercedes sold fewer than 2,000 SLKs in the U.S. in 2010, so chances are good that the company will find at least that many buyers with this updated car. They won't be giving up their Boxsters this time either, but they will be getting a car that makes an everyday drive feel like being on vacation.

Edmunds attended a manufacturer-sponsored event, to which selected members of the press were invited, to facilitate this report.

Price and Build Your Own 2012 Mercedes-Benz SLK350 at Edmunds.com