Mercedes-Benz recently flew a bunch of Canadian automotive writers, myself included, to picturesque and leafy-green Manchester Village, Vermont, for the unveiling of the face-lifted M-Class, or ML 320 specifically. The small, nature-embracing town was the perfect backdrop for the event, seeing as the hoopla surrounding the launch wasn’t so much geared toward the vehicle as it was the new technology behind it—BlueTEC—an eco-friendly, clean diesel system pioneered by Daimler AG.

Now, that’s not to say that the new M-Class isn’t worth mentioning. The “facelift” isn’t substantial, but then again, the previous incarnation of the mid-size SUV was near-perfect anyway. After all, why mess with a good thing?

Ch-ch-ch-ch-changes

Some of the more notable (or should I say, noticeable) enhancements include a new-look, robust front bumper, a larger, lower-set radiator with three large, silver rectangular air outlets and roof rails that are now included as a standard exterior spec. A new, stainless steel underguard conceals the exhaust system, giving it a sporty, off-road-worthy appearance.

The interior has been enhanced with a new, four-spoke leather steering wheel with chrome trim and buttons to operate just about every feature the vehicle offers. The seats have also been tinkered with and provide a more comfortable, snug fit than the previous model. And the new standard 6.5-inch colour display has been upgraded with a twin tuner for improved radio reception, speed-sensitive volume control and Bluetooth interface for hands-free communication.

While the front passengers are rocking out to the sweet sounds from the 610-watt Harman Kardon Logic7 sound system, the rear seat passengers will keep entertained with the optional new entertainment system with two, eight-inch screens and centrally integrated DVD player. Also included are two sets of headphones and two remotes.

But by the end of the event, the most impressive feature of the company’s most successful sport ute was its V6 diesel BlueTEC engine mated to a 7G-TRONIC automatic transmission. (If you fancy yourself a fan of the petrol, don’t worry, you also have a choice between a substantial V6 or a powerful V8.) Not only did the ML 320 BlueTEC’s engine perform well on both highway and off-road conditions—210 horses, 400 lb-ft at 1,600 rpm—it also offers better-than-gasoline fuel economy numbers (11.3/8.3 L/100km city/highway).

So the question is: How can a V6 diesel-powered SUV produce four-cylinder fuel economy numbers while delivering eight-cylinder performance? Let’s pop the hood to find out.

The green thing about blue

BlueTEC was first introduced to North America in 2006 with the E 320 BlueTEC. It proved to be a massive success, garnering the vehicle an award in 2007 for “World Green Car of the Year.” So it comes as no surprise that the company has decided to introduce three new models – R, ML and GL 320 – with the eco-friendly technology.

The key ingredient to the new BlueTEC system is AdBlue – an aqueous urea solution that’s injected from a separate, 28-litre onboard tank directly into the stream of exhaust. When injected into the hot, pre-treated exhaust fumes, AdBlue is first broken down into water and urea. At around 170 C, the urea is converted into ammonia, the actual active agent in this process. The ammonia is stored in the catalytic converter and reduces the nitrogen oxides (pollutants) into harmless nitrogen when it passes through. Pretty cool, eh? And the only effort you have to put in to saving the planet is turning the key to the ignition.

Now, I know what you’re thinking (likely the same thing as all of the other automotive scribes on hand at the press conference): How often will AdBlue need to be topped up and how much will a refill cost? According to Mercedes-Benz, the average consumption of AdBlue is only around 0.1 litres per 100 kilometres (or roughly one to three per cent of diesel consumption) and only needs to be refilled at the dealership during regular service intervals. As for the price, Mercedes-Benz claims “it’s not going to cost an arm and a leg.” Exact pricing information is not available. Let’s hope it’s cheaper than an arm or a leg, too.

And although the engine will run “fine” without adding AdBlue, you’ll wilt more trees than a California brush fire with the pollutants emitting from the exhaust. However, Mercedes-Benz has developed a foolproof sensor that will only allow you 20 start-ups with an empty AdBlue reservoir. After that, your ML (or R or GL) will fail to start—until you add the solution once again.

According to Mercedes-Benz, the company has offered the BlueTEC patent to the entire automotive industry—and why not? The new ML 320 BlueTEC performed at a higher level than other competing diesel or gasoline-based SUVs without the attributed guilt. BlueTEC lets you enjoy driving your SUV without feeling like you have to slump down in the seat as others drive by. There’s no shame here. Feel free to drive through Manchester Village any time you like in one of Mercedes’ latest. The trees will thank you.