It wasn't long ago that diesel vehicles were so deafening that conversations had to be yelled, so polluting that standing behind a tailpipe could get you a dusting of fine particulate. It's an archaic image that has helped keep sales of diesel passenger vehicles to a mere 3 percent of the U.S. So with its GLK250 BlueTEC, Mercedes-Benz is pulling out all the stops. At today's per-gallon diesel prices, that's like getting 14,000 miles of driving for free. Drivers just need to buy the car first. The smallest SUV in the Mercedes lineup now has one of its smallest engines: a 2.1-liter inline four. That engine packs a lot of punch because it's direct-injected, twin turbocharged and diesel -- all of which work to decrease emissions while boosting off-the-line performance and miles per gallon to an Environmental Protection Agency-estimated 28 combined. More energy-dense than gasoline, diesel is almost magical in its performance, specifically in terms of torque. It does, however, reduce the car's horsepower to a mere 200, which, despite Americans' obsession with big giddyap, has little bearing on daily driving since the United States lacks an Autobahn to max out the GLK's 130 mph top speed.

It wasn't long ago that diesel vehicles were so deafening that conversations had to be yelled, so polluting that standing behind a tailpipe could get you a dusting of fine particulate. It's an archaic image that has helped keep sales of diesel passenger vehicles to a mere 3 percent of the U.S. So with its GLK250 BlueTEC, Mercedes-Benz is pulling out all the stops. At today's per-gallon diesel prices, that's like getting 14,000 miles of driving for free. Drivers just need to buy the car first. The smallest SUV in the Mercedes lineup now has one of its smallest engines: a 2.1-liter inline four. That engine packs a lot of punch because it's direct-injected, twin turbocharged and diesel -- all of which work to decrease emissions while boosting off-the-line performance and miles per gallon to an Environmental Protection Agency-estimated 28 combined. More energy-dense than gasoline, diesel is almost magical in its performance, specifically in terms of torque. It does, however, reduce the car's horsepower to a mere 200, which, despite Americans' obsession with big giddyap, has little bearing on daily driving since the United States lacks an Autobahn to max out the GLK's 130 mph top speed.

The GLK's diesel engine is most apparent at idle, when, with the stereo off, drivers can hear the faint purr of the engine's compression ignition firing the fuel, and on takeoff, which is V-8-like in its velocity. The turbocharger operates in two stages and is enhanced with an intercooler that chills the air before it's stuffed back into the combustion chambers. The result is a significant increase in jump-the-green grunt without any discernible lag. Despite the recent adoption of the term "crossover" to describe smallish, all-wheel-drive utility vehicles, Mercedes still refers to the GLK as an SUV, the stature of which looks like an oversized station wagon and drives like a tallish sport car. Its permanent all-wheel drive, or 4Matic, as Mercedes calls it, isn't so much a traction-control system as a handling enhancement that's tireless in its efforts to aid cornering. Driving diesel is like having your cake and eating it too. With its well-priced, high-mileage GLK250, Mercedes-Benz serves it up with ice cream.

Our short test drive, 80% of which took place on the highway (at 120 km/hr), gave us an average of 11.4. The V6 is equipped with Start/Stop technology that shuts down the engine when ECO Mode is activated. Too bad the diesel doesn鈥檛 offer that feature. Interestingly, both the 2.2- and 3.5-litres can tow 1,588 kg (3,500 pounds). Basically, customers have to decide what鈥檚 more important: fuel consumption (and the driving range) of their GLK or its performance. As for the ride, diesel or not, it鈥檚 tough to find fault with the GLK - though the V6 is indeed a little faster both in terms of accelerations and pick-up. Although the diesel has a far superior torque, its pick-up is less powerful. The 80-120 km/h time, after a quick manually timed test, was 7.31 for the GLK250 and 5.28 for the GLK350. However, the 250 is better suited for off-roading (and by off-roading, I don鈥檛 mean the bumpy, muddy road leading up to your cottage, I mean real off-roading). Tanks don鈥檛 come cheap! As for the rest, GLK is classic Mercedes-Benz. 2,400), the central screen is surprisingly small for a vehicle whose dashboard was just redesigned - and it鈥檚 not even a touchscreen! Finally, the quality of the materials and finish is exceptional. 44,900, respectively. But you can bet your bottom dollar that the total cost will be much higher!

Mercedes-Benz announced their plans to offer a four-cylinder petrol GLK that will go on sale this June. The Mercedes GLK 250 4MATIC will feature a turbocharged 2.0-liter four-cylinder engine that will offer up 211 HP (155 kW) and 350 Nm (258 lb-ft) of torque. The turbocharged engine will propel the GLK250 from 0-100 km/h (0-62 mph) in 7.9 seconds on its way to a top speed of 215 km/h (133 mph). As for the mini SUV鈥檚 efficiency, you can expect an average of 30.5-31.3 mpg. Enhancing the range of engines available for the GLK is a particularly agile and fuel-efficient four-cylinder petrol unit. With an output of 155 kW (211 hp) and torque of 350 newton metres, this state-of-the-art direct injection engine in the GLK 250 4MATIC delivers effortlessly superior performance and well-balanced drive comfort. The new model year also brings the added benefit of a new-generation infotainment system with extended functionality for the GLK-Class, as for all SUV models from Mercedes-Benz.

From June 2013 the GLK range will, for the first time, feature a four-cylinder petrol engine. This high-tech 2.0-litre unit offers the impressive drive comfortthat is such a typical feature of the brand, at a level comparable to that of the V6 petrol unit in the GLK 350 4MATIC. Its performance is similarly impressive. The GLK 250 4MATIC accelerates from 0 to 100 km/h in 7.9 seconds and can reach a top speed of 215 km/h. In doing so, the new model boasts an NEDC combined fuel consumption of just 7.7 to 7.5 litres of unleaded petrol per 100 kilometres (180-176 g CO2/km). The new model owes its impressive efficiency to a comprehensive package of measures. As well as the combination of exhaust gas turbocharger and direct injection, these include the low engine weight of 139 kilograms, low friction losses and the demand-actuated control of the ancillary units. Fast-acting piezo injectors make multiple injections of fuel possible, while reliable combustion of the air/fuel mixture is ensured by demand-actuated multi-spark ignition. In addition, variable valve timing on the inlet and exhaust side has the effect of reducing consumption as well as enhancing output.