BBC Autos

Joyride

Is this Mercedes' best-kept secret?

About the author

Editor of BBC Autos, Matthew is a former editor at Automobile Magazine and the creator of the digital-only Roadtrip Magazine. His automotive and travel writing has appeared in such magazines as Wired, Popular Science, The Robb Report and Caribbean Travel + Life. He lives in Los Angeles with his wonderful wife and four-year-old daughter.

 

HIDE CAPTION

In the US, the diesel-powered passenger car is, and always has been, an acquired taste. Its engine sounds different than a gasoline-powered car’s, and it certainly smells different, and fill-ups, particularly when rubbing shoulders with truckers at highway truck stops, is, well, really different.

But a week with the 2013 Mercedes-Benz ML350 BlueTEC – days that featured a good many lazy highway miles during which the fuel-gauge needle barely budged – reinforced the essential appeal of civilian diesels. And the ML is one of the nicest. Accounting for a meager 15% of M-Class sales in the US, the ML350 BlueTEC may be the automaker’s best-kept secret.

There are currently five versions of Mercedes’ middle-sized sport-utility vehicle: rear- and all-wheel drive gasoline V6 models, two all-wheel-drive V8 models, and an all-wheel drive diesel V6 model. It is this last variant, the ML350 BlueTEC, that may be pick of the litter. It is not as hushed as the gasoline-fed ML350, or as sonorous as the V8-powered ML550, or as brutally swift as the 518-horsepower ML63 AMG. But the diesel-sipping ML is as refined as its siblings, quick enough to stay in the pack and more frugal than any of them.

While the smelly blue smoke of diesel’s olden days has cleared, thanks to a variety of emissions-reducing technologies, the characteristic noise of Rudolf Diesel’s creation persists. Considerably more “diesel-sounding” than the 2.1-litre twin-turbo four-cylinder diesel in the new GLK250 BlueTEC, the ML350 BlueTEC’s V6 presents a muted, but unmistakable, diesel clatter at idle. And at full-throttle, the 5,038lb SUV does a fairly cunning imitation of one of its 18-wheel corporate siblings from Freightliner. The noise is never obnoxious or overbearing however; it emerges, in fact, as one of the nostalgic charms of the diesel ML. Mercedes-Benz and diesel engines go back to the 1930s, and over the decades the company’s “oil-burners” have earned a reputation for indefatigable reliability. The clatter-roar of a spooled-up ML350 BlueTEC imparts a sense – real or imagined – of peerless fortitude and utter indestructibility.

Like most diesels, the ML350 BlueTEC is all about torque. The engine produces a modest 240 horsepower (the least of all M-Class models), but churns out a hearty 455 pound-feet of torque – a figure that tops the V8-powered ML550’s 443lb-ft, and tickling the beastly ML63 AMG’s monumental 517lb-ft. Unfortunately, the diesel ML’s prodigious oomph does not equate to prodigious speed; its 7.5-second dash to 60mph is equal to that of the gasoline-powered six-cylinder ML350, and more than two seconds behind the V8-powered ML550. Nor does it equate to greater towing capacity: all ML models are rated to tow 7,200 pounds, save the odd-duck rear-wheel-drive version of the ML350, which manages only 6,600lbs.

Where the ML350 does achieve heroic status, however, is on the open road. Diesel-powered models are any automaker’s most long-legged offerings, and the ML350 BlueTEC 4Matic is no exception. Returning 28mpg on the Interstate (handily topping the ML350 4Matic’s 23mpg and the ML550 4Matic’s 20mpg), the ML350 BlueTEC, equipped with Mercedes’ familiar 7G-Tronic seven-speed automatic transmission, makes the most of its 27.7-gallon fuel tank.

Range between fill-ups exceeds 700 miles — that amounts to Washington DC to Chicago on a single tank.

The cabin of the new ML is a very fine place to while away the miles. When the first generation of the Tuscaloosa, Alabama-built M-Class debuted for the 1998 model year, all was not well. The interior was atypically cheap in spots, and the driving experience was decidedly minivan-like – which, for those unfamiliar with minivan driving dynamics, is not a good thing. In two subsequent generations, the latest arriving as a 2012 model, the ML has fully remedied what ailed it. Interior quality is on par with that of the E-Class – which is to say, marvelous – and the SUV manages the neat trick of feeling both nimbler and burlier at the same time. The experience is, in the words of Goldilocks, just right.

As a footnote, it bears mention that the ML350 BlueTEC’s engaging engine is available in the larger GL-Class SUV, a vehicle that recently earned Motor Trend magazine’s 2013 SUV of the year award. It, too, is a very fine vehicle, doing everything the ML does, but with a third row of seats. Then again, the GL350 BlueTEC (the GL’s base model) starts a not-inconsequential $11,130 higher than the ML350 BlueTEC. To put that figure in more workaday terms, $11,130 is equal to roughly 100 tanks of fuel – or some 70,000 highway miles.

Vital stats: 2013 Mercedes-Benz ML550 BlueTEC 4Matic

  • Base price: $52,175, inclusive of $905 destination charge
  • As tested: $64,965
  • EPA fuel economy: 20mpg city, 28mpg highway
  • Drivetrain: 240hp, 3-litre turbocharged V6 diesel engine, seven-speed automatic transmission, all-wheel drive
  • Major options: Parktronic parking assist, $970; Harman/Kardon audio system, $810; brushed aluminum running boards, $670; Premium package (80GB hard-drive navigation with Zagat Survey; MP3 media interface; SiriusXM with traffic and weather; enhanced voice control for audio, telephone and navigation systems; 10-way power driver seat with memory; power tilt/telescoping steering column; auto-dimming driver-side and rear-view mirrors; double sun visors, 115V power outlet in rear seating area; rear-view camera), $3,700; Lighting package (bi-xenon headlamps with active cornering, headlamp washers and active high-beam assist), $1,290; Driver Assistance package (active cruise control, blind-spot assist, active lane-keeping assist, brake assist system, collision mitigation system), $2,950; panorama roof, $1,090; wood/leather steering wheel $590
The diesel-sipping ML is as refined as its siblings, quick enough to stay in the pack and more frugal than any of them.