2009 Mercedes-Benz M-Class Review

Forget everything you ever thought you knew (and wanted to forget) about diesel vehicles. From the Mercedes-Benz shake-rattle-and-roll diesel powerplants of the '80s to the uncomfortably putrid, unmistakable signature odor dispelled from the exhaust, there's very little that can be said that would be complimentary of the "old" diesels. Thankfully, with incredible engineering, amazing technological advances and a consciousness discreetly looking over its shoulder at a growing "green" awareness, Mercedes-Benz delivers the 2009 ML 320 BlueTEC -- their cleanest diesel ever.

It doesn't take much to build my anticipation when I look at my schedule and see there is a Mercedes-Benz arriving. It is quite another thing when you realize that the classy cruiser, the always-luxurious Mercedes ... has a diesel engine. It's like your favorite dessert arrives with coconut sprinkled all over it - and you are allergic to coconut.

Of course, I'm playing up my initial expectations for the BlueTEC diesel engine on the 2009 ML 320. It has always been that way for the 20-or-so diesels I've reviewed over the years. Perhaps 'intrigued' would be the extent I'd be willing to go to describe my level of expectation after starting up the engine.

An hour later that would fade to black, as in the color leather in my tester. 'Intrigued' turned to "impressed" and the new BlueTEC turned out to be but a figment of past annoying diesel engines. The air outside was clearly cleaner, less pungent and my neighbors didn't get woken up from their peaceful slumbers each morning at 6 a.m. when I fired it up.

The BlueTEC is so clean it can be sold in 50 states, including benchmark California. So what all the sudden happened to make this Mercedes-Benz so much cleaner? And what exactly is BlueTEC. Simply, an exhaust treatment called AdBlue does the trick by breaking down the dirty exhaust into its own solution parts of water and urea. I'm told the urea converts to ammonia, which in turn breaks down the bad nitrogen oxide gasses into less offensive and less dangerous nitrogen. The BlueTEC name is simply the Marketing department's spin on the less impressive AdBlue moniker for the process. The really key thing to remember is that all this blue -- is really green.

The ML 320 is an attractive five-passenger sport utility vehicle that will get lots of attention for what is under the hood and definitely for what is not coming out the tailpipe. The BlueTEC diesel in my tester was a 3.0-liter turbodiesel V-6 engine (201 horsepower at 3,400 rpm) mated to a 7-speed automatic transmission.

My tester's turbodiesel V-6 generated outstanding torque of 398 lb.-ft. at a low range of 1,600 rpm into 2,400 rpm. This is what diesels have always brought to the party and you can really feel it when you jab the accelerator. All that torque delivers the pulling strength of a V-8, making it ideal for towing. This ML 320 BlueTEC's tow rating is 7,200 pounds, which is excellent for this size SUV.

Base price for the ML 320 BlueTEC is $48,600. My tester had about $9,000 in optional equipment that brought the cost, including destination charge, to $58,885. It is pretty steep, it is more than most anything relatively close in size, but it is a Mercedes-Benz and the BlueTEC diesel does make it special.

Also special on the ML 320 is the level of comfort, convenience and safety afforded passengers. Having had this tester during some of the coldest days in Chicagoland, there was nothing more rewarding than to push the start button on the intelligent key system and listen to the engine turn over. While the exhaust is clean, the noise of the diesel engine is still probably the remaining flaw. It is not annoying, but noticeably louder and rougher from a cold start.

Standard safety equipment includes Mercedes' impressive Pre-Safe system that is able to sense an impending crash and prepares the car to become ultra-safe. The Pre-Safe system will close the side windows so the side curtain airbags better deploy and protect passengers as well as an automatically closing sunroof in the event of a rollover.

Inside the ML 320 you find lavish leather surrounding and enveloping you in comfort. The cabin is quiet and cozy with power adjusts for driver and passenger, a heated leather steering wheel, and heated leather seats for front and rear passengers ($1,390). At $3,850, the P01 Optional Package is probably the one you might second guess whether you need, but believe me, if you are going this far you might as well go all the way and snap it up. Featuring the rearview camera, nav system, Harman-Kardon audio upgrade surround sound and iPod adaptors, it is essential.

The ML 320 holds 25 gallons of diesel fuel with a potential cruising range of about 600 miles. The EPA rated fuel economy is 18 miles city and 24 miles highway, with a combined rating of 20 mpg. Diesel is pretty common at most gas stations, especially those off any highway, so one should not be concerned about being able to get fuel.

This BlueTEC ML 320 is a technological marvel. I can only hope they do not stop pressing the engineers to get more miles and even cleaner exhausts down the road.