Mercedes-Benz shows off diesel with GLK250

The Mercedes-Benz GLK250 BlueTEC 4 MATIC, which has a diesel engine, gets 33% better fuel economy than its petrol-powered counterpart.

By Susan CarpenterIt 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% of the US 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 an SUV with a four-cylinder diesel engine that gets 33% better fuel economy than its petrol-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 (in the US).The smallest SUV in the Mercedes lineup now has one of its smallest engines: a 2.1-litre 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 mpgs to an EPA-estimated 28 combined. The same engine will be offered later this year in both the redesigned E-class and Sprinter van, which speaks to its power.More energy-dense than petrol, 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 US 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 between the moment a lady goes heel-to-toe and the split-second later when she jettisons across the asphalt. The GLK250 BlueTEC reaches peak torque between just 1,600 and 1,800 rpm.Despite the recent adoption of the term “crossover” to describe smallish, all-wheel-drive utility vehicles, Mercedes still refers to its smallish, all-wheel drive 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.The GLK’s Standard Agility Control uses shocks with bypass pistons that, in my morning with the GLK, didn’t entirely nullify the effects of poorly maintained roads but were effective at convincing me the cracks and potholes and rubble might not need immediate attention. Off road, the pistons that smooth the street effects are bypassed to allow the full effect of the shocks to do their work.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 needing to refuel.First introduced in 2009, the GLK was redesigned last June with an updated interior that includes a new air vent design lifted from aviation, a repositioned gear shift from centre console to steering wheel stalk, a new colour instrument display and lots and lots of buttons. The GLK is available with a 7-inch display screen, but it isn’t operated by touch. Drivers can command the Nav, radio and other features with steering controls and voice commands or do it old school, with buttons and knobs.My GLK test car was fully loaded with $18,000 worth of optional amenities that make the living easy, including Harman/Kardon audio, a backup camera, 7-inch colour display and heated leather seats coloured clotted cream and trimmed in chocolate, as well as a driver-assistance package that let me know when cars were in my blind spots and beeped whenever I was about to hitch my front end to a stranger’s bumper.Already, 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. — The Orange County Register/MCT*  (Price and technical specifications may vary in locally available models)