While the satellite radio and iPod interface will keep you entertained in traffic, the superb drivetrain will put a smile on your face when you finally get out of town. In the hills above Malibu, the 268-horsepower V-6, seven-speed automatic transmission, and 4Matic all-wheel drive system make the GLK350 a surprisingly sporty ride. While the steering is, in typical SUV fashion, rather slow (2.75 turns lock-to-lock,), it's accurate. The big Pirelli meats offer impressive grip, and even when they began to let go, stability and traction control quickly reeled in the errant wheels. At the track, all that grip, plus surprisingly flat cornering, translated to an impressive 0.80 g of lateral acceleration and an equally impressive 28.1-second lap time around the Motor Trend Figure Eight.
The transmission rocks. While the GLK's seven-speed auto allows for manual shifting by rocking the shift lever left to right, driver input really isn't necessary. Switch the vehicle from Comfort Mode to Sport mode and the seven-speed will hold gears longer, allowing quick bursts between turns without ever changing cogs.
On the track, the 3.5-liter V-6 hustled the Benz to 60 mph in just 6.6 seconds. Stops were equally impressive: 60 to 0 mph in just 124 feet. Brake-pedal feel left much to be desired, though. The first half of travel is mushy and provides little stopping power. Then, forces suddenly firm up considerably and the brakes bite hard. The GLK needs a more gradual, linear braking response.
To their credit, the brakes have a tough job. Despite its smallish size, the GLK tips the scales at 4214 pounds. Still, the GLK never feels like a porker. Merging and passing on the freeway are effortless, and the GLK can pull off a 15.0-second quarter-mile at 92.9 mph. The real penalty is fuel economy: The GLK carries an estimated EPA city/highway rating of just 16/22 mpg. And it only drinks premium.