The 2013 Mercedes-Benz GLK350 is the closest thing that we've got this generation to a wagon version of the C350 sport sedan with which it shares its platform and 3.5-liter, V-6 engine. "But wait," you're probably saying as you look at the photos above, "isn't that a big SUV?"
I can understand your confusion; conventional wisdom dictates that crossovers are bigger than sedans, but let's take a look at the numbers. The GLK's 178.3-inch overall length, 108.5-inch wheelbase, and front and rear track are actual slightly smaller than the C-Class' measurements. Of course, the crossover is still wider by about 5 inches and taller by about 10 inches than the sedan and the whole package is at least 463 pounds heavier depending on options -- our 4Matic all-wheel-drive-equipped tester was probably slightly heavier still.
The taller GLK still fits in a C-Class sized parking spot, but has significantly more cargo room (between 23.3 cubic feet and 54.7 cubic feet, depending on whether you fold the rear seats flat), more passenger room, and a higher, more commanding view of the road.
Power and efficiency
The extra mass and taller, slightly less aerodynamic profile adds a few ticks to the 0-60 time and subtracts a few from the fuel economy estimates, but we'll come back to that momentarily.
Peek under the GLK's hood and you'll find the same 3.5-liter V-6 engine that powers the C350 Sports Sedan. This naturally aspirated mill uses direct-injection technology to attempt to optimize power and fuel efficiency. Output is estimated at 302 horsepower and 273 pound-feet of torque.
Torque exits the engine via a single-option seven-speed automatic transmission before heading to the wheels. Just which wheels provide motivational duties depends on which drivetrain option box you checked at the dealership. The standard configuration sends power through the rear wheels, but a $2,000 4Matic all-wheel-drive package splits power between the front and rear wheels. This is a permanent all-wheel setup with a default front-rear torque split of 45/55, but up to 70 percent of available torque can be temporarily shuffled to either axle as traction needs dictate.
The GLK's transmission lacks a manual shift mode -- there are steering-wheel paddles and its steering-column-mounted shifter only has stops for PRND -- but it does feature two shift programs, Sport and Economy. The primary difference between these modes is that one (Sport) lets the tachometer sweep closer to its redline before shifting to take advantage of the available horsepower at higher engine speeds. Sport program will also downshift more readily when asked to accelerate and, occasionally, when braking in anticipation of a turn. The other program, Economy, short-shifts every gear, hustling to top gear as quickly as reasonably allowable to keep revs low and fuel economy up.
There's also an Eco Start-Stop system system present on the GLK350 that will shut down the engine when the vehicle comes to a complete stop to prevent wasting fuel while idling. During my driving time, the system only seemed to activate when the engine was sufficiently warmed up, and the restart was smooth and effortless under most conditions. When restarting after sitting at a traffic light or stop sign, the engine would fire up in the time it took my right foot to ease from the brake to gas pedal and acceleration would resume without a hiccup. The only indicator that anything special was happening was a slight cough from the engine that you wouldn't even really hear with the windows up and audio system playing. However, when the system started repeatedly activating during a stop-and-go traffic crawl, I became aware of a slight shudder that passed through the vehicle if I didn't give the system time to do its thing. Fortunately, the button to defeat the Eco Start-Stop during conditions like that is handily located on the dashboard.
Fuel economy for our 4Matic-equipped model is estimated at 19 city mpg, 24 highway mpg, and 21 mpg combined. Skip the all-wheel drive in favor of a rear-driven model and you can add 1 mpg to the highway estimate. Those efficiency estimates aren't particularly heinous, but the middle-of-the-pack averages aren't much to get excited over either. Also factor in that Mercedes-Benz recommends that the GLK350's 17.4 gallon tank be filled with premium gasoline, which very slightly increases operating costs.
Handling and comfort
Around town, the GLK350 handles like the vertically stretched C-platformed vehicle that it is. Differences in suspension tune give the crossover a smooth ride that dulls the worst bumps. However, it's still firm enough that you don't forget that the bumps are there. A bit of that firmness is probably due to the optional 20-inch wheels (though I can't imagine that the stock 19-inchers are significantly smoother), but most of the thanks and blame should fall on the stiffly damped suspension system. The tradeoff for a slightly bumpy ride is that GLK does offer good responsiveness when dodging potholes and minimal squat and dive when accelerating or braking at intersections.
This is all assuming that you're driving like a sensible person (or at least being smooth with your inputs). Get too lead-footed with jackrabbit starts and panicked stops or saw away at the steering wheel and the GLK350's elevated center of gravity and the laws of physics will gang up on you.
The tall seating position of a crossover is a godsend for seeing over and around parked cars when easing out of blind alleys into traffic and 360-degree visibility is good thanks to the airy greenhouse and large windows. However, despite its parkable footprint, I found it difficult to spot the GLK's corners during parallel parking maneuvers. Erring on the side of caution, I'd often end up further from the curb than intended, but it would be just as easy to scuff those shiny 20-inch wheels on a high curb.