BlueTEC Added to Mercedes-Benz Diesel SUVs

Here in North America, Mercedes-Benz offers more diesel-powered vehicles

than any other brand, a title that used to belong to Volkswagen. What's more, all of Mercedes-Benz's SUVs, with the exception of the limited production G-Class, are offered with a diesel under the hood, including the ML-, GL- and R-Class. They feature the third-generation common-rail turbodiesel V6 “320 CDI” series engine, which makes 215 horsepower and a jaw-dropping 398 lb-ft of torque. The only problem with this situation is that none of these diesel-powered SUVs offers Mercedes' BlueTEC exhaust system, which would otherwise allow them to meet Tier 2 Bin 5 and forthcoming Euro6 emissions standards, as with the E320 CDI Bluetec sedan. This, however, will change as new models arrive in autumn.

As with the forthcoming Audi Q7 V6 TDI and Volkswagen Touareg V6 TDI, the upcoming Mercedes-Benz diesel SUVs will feature the AdBlue exhaust after-treatment system, which involves an SCR catalytic converter plus the

AdBlue injection system to reduce NOx tailpipe emissions. To accommodate the system, Mercedes-Benz altered the engine slightly with new piston crowns, and a reduce compression ratio (16.5:1 vs. 17.7:1). The engine's ECU has also been re-calibrated to improve combustion, and while horsepower is reduced slightly to 211 horsepower, torque remains the same at 398 lb-ft.

On the ML and R-Class, the AdBlue tank is 7.4 gallons, with the GL's tank slightly larger at 8.5 gallons. And, as with the E320 BlueTEC, there is no maintenance on the part of the owner, with the tank being filled up at scheduled maintenance intervals. The new BlueTEC SUVs will initially be offered in North America, though their availability will be made worldwide later on.