Mercedes-Benz Diesels

Mercedes-Benz has formally announced the launch of the ML320 CDI, R320 CDI and E320 Bluetec diesel models, a precursor of sorts to what it has planned for its diesel future in the U.S. The launch follows the passing of the Oct. 15 deadline for the availability of Ultra-Low-Sulfur-Diesel (ULSD) fuel at pumps across the country.

All three vehicles use a 3.2-liter diesel V6, which pumps out 215 hp and 398 lb-ft of torque in the ML and R-Class. The version in the E-Class produces 208 hp and 400 lb-ft of torque and is equipped with Mercedes' Bluetec emissions control system. This system uses a number of techniques to curb engine emissions, including a particulate filter, common-rail direct fuel injection, and variable-geometry turbochargers. A key piece of the future plan is the not quite fully-developed AdBlue urea-injection system for reducing nitrogen oxide emissions, key to getting future-diesel powered Benzes certified nationwide.

The ML320 and R320 are similarly priced at $44,455 and $44,775, respectively, while the Bluetec E320 begins at $52,325. These prices are close to their gas-powered cousins -- enabling consumers to get superior fuel-efficiency without paying a serious premium often associated with hybrids.

As a comparison, the gas-powered E350 gets EPA fuel economy ratings of 19/26 mpg city/highway. The diesel E320 does much better, achieving 27/37 mpg city/highway, similar to the fuel economy achieved by the compact Toyota Corolla.

At present, none of the cars are able to meet emissions standards in California, New York, Maine, Vermont and Massachusetts, though Mercedes has previously announced that it will have BIN5 compliant diesel models of the ML, GL, and R-Class for the 2008 model year using the Bluetec engines equipped with the AdBlue system. When enacted in 2009, the BIN5 standards will be the strictest in the world. Unlike the recently unveiled vehicles, the next-generation models will be available for sale in all 50 states.

The Bluetec system will also soon be seen in offerings from the three other German companies. Volkswagen, its Audi subsidiary and BMW are all, along with Mercedes, working on a strategic alliance designed to drive the popularity of diesel models in the U.S. In addition to the Mercedes models, a number of other Bluetec-powered vehicles will be on display at the upcoming Los Angeles Auto Show, including the Audi Q7, BMW X5, and Volkswagen's new Tiguan compact SUV. A Bluetec-powered concept version of the Jeep Grand Cherokee will also likely be on the stand in L.A. as well.