The 2007 Mercedes-Benz ML320 CDI is further proof that diesel engines nowadays are refined as well as efficient. This midsize SUV provides fuel economy in addition to the platinum-card luxury you would expect.

Photo by Mercedes-Benz (ENLARGE)

Mercedes-Benz ML320 CDI

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ABOUT THE MERCEDES-BENZ ML320 CDIA:

Body style: Regular, extended cab and crew cab pickup truck

Price: $44,455

Drive: Four-wheel

Engine: 3-liter V-6 diesel

Transmission: Seven-speed automatic

Miles per gallon of fuel: 21 city / 27 highway

WHAT'S SPECIAL: The 3-liter, V-6 diesel engine uses common-rail direct injection (that's the CDI in the SUV's name) that helps the engine burn cleaner and quieter. When starting on a cold morning, there is a bit more idle clatter than a gasoline engine, but not enough to notice when you're inside the comfortable cabin.

WHAT WE LIKE: This is an SUV of Goldilocks proportion -- big enough to comfortably haul five adults and their gear; small enough to comfortably maneuver through a downtown parking lot. The power rear liftgate is one of many nice touches.

WHAT ISN'T THERE: A quick start. While the diesel is built for pulling -- generating 398 pounds-feet of torque -- starts from the stoplight are stately. The 0-60 mph time is a hair over 8 seconds. Want thrills? Go with the 503-horsepower ML63 AMG.

YOU OUGHTA KNOW: Help is available with the push of a button. The Tele Aid system uses GPS plus, a cellular telephone link to summon help, similar to the General Motors OnStar system. A big SOS button is mounted on the overhead console. Buttons to connect to roadside assistance and information services are located in the center console. The system will also track your SUV if it is stolen.

EXTRAS: As you might expect in a Mercedes-Benz, the list of features is long. There is dual-zone climate control with rear-seat controls, navigation system, eight-way power adjustable front seats and eight-speaker Harmon Kardon sound system. There are heated seats front and back and, especially appreciated on recent cold mornings, a heated steering wheel. This SUV is also loaded with safety features including window curtain side air bags.

AND ANOTHER THING: The M-class sport utility vehicles may be designed in Germany, but they are built in Tuscaloosa, Ala.