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. market.
So with its GLK250 BlueTEC, Mercedes-Benz is pulling out all the stops. For the first time in 80-plus years of building diesel cars, it's offering Americans a sport utility vehicle with a four-cylinder diesel engine that gets 33 percent better fuel economy than its gas-powered counterpart -- and costs $500 less.
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 GLK250 BlueTEC 4MATIC starts at $38,550.
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.
In daily use, the roof rails and skid plates serve mostly as a reminder that, yes, the GLK would happily detour from its grocery store to elementary school to soccer practice loop and scramble out of state, up a dirt road and into a camp site as far away as Tucson. The GLK250 can travel up to 515 miles without refueling.
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.
2013 MERCEDES-BENZ GLK250
Base price: $38,550
Price as tested: $56,730
Engine: 2.1-liter, inline four-cylinder, variable valve timing, direct injection, biturbo diesel
Power: 200 horsepower at 3,800 rpm
Maximum torque: 369 pound-feet at 1,600 to 1,800 rpm
Length: 178.3 inches
Wheelbase: 108.5 inches
Towing capacity: 3,500 pounds
Top speed: 130 mph
0 to 60 mph: 7.9 seconds
EPA fuel economy: 24 mpg city, 33 highway
Bottom line: High-performance diesel, attractive price