Mercedes-Benz ML-, GL-, and R-Class diesels head to the U.S.

Mercedes-Benz is revving up its U.S. market diesel push by offering its ML320 BlueTEC, GL320 BlueTEC, and R320 BlueTEC diesels to American consumers before any other market gets the vehicles. All three Benzes are powered by a 3.0-liter, 211 horsepower turbo V-6 generating 398 lb-ft of torque. Mated to Benz's seven-speed automatic transmission, all three people-movers will meet the U.S. Bin 5 standard as well the European EU6 standard, Mercedes says.

The diesel at the heart of the efficient trio utilizes Mercedes' AdBlue technology, which involves injecting an aqueous urea solution into hot, pre-treated exhaust gases. The process helps reduce nitrogen oxides -- a harmful exhaust gas found in high levels in diesels -- into nitrogen after the exhaust gasses pass through the catalytic converter. The tank carrying the solution is monitored by the engine management system. Since the tank only needs to be refilled at regular service visits, no extra maintenance is required for a GL320 BlueTEC over a GL450 or any other Mercedes SUV.

So what's the result of all this technology? An ML320 BlueTEC goes from 0-60 mph in 8.5 seconds while achieving 18/24 mpg. The R320 BlueTEC matches the ML's fuel economy numbers and gets from 0-60 one tick later at 8.6 seconds. The larger GL320 BlueTEC scoots from 0-60 mph in 9.2 seconds with expected fuel economy numbers of 17/23 mpg. For comparison, an ML350 4matic gets 15/20 mpg while the current ML320 CDI diesel matches the more advanced ML diesel at 18/24 mpg, but not in emissions. Both of the existing MLs go from 0-60 mph in about eight seconds. The Chevy Tahoe Hybrid 4WD straddles the new Mercedes diesels in fuel economy at 20/20 mpg, but you can bet the upcoming Cadillac Escalade will not match those figures. Regardless, the Mercedes diesels will be at their best when out on the highway cruising at a steady speed. Hybrids, by contrast, are not as efficient on highways, or at least on those rare occasions when highways don't have traffic.

For now, it appears that Mercedes will have the luxury diesel SUV market all to itself if the three new diesels hit their scheduled fall 2008 U.S. release date. We wonder if (when?) the GLK will eventually get a diesel for the U.S. market. The important question remains: will consumers see the competent, premium SUVS beyond their preconceptions about diesels?