At a public hearing today in Los Angeles, the Alliance of Automobile Manufacturers commended the direction of the U.S. Environmental Protection Agency's (EPA) proposed rule on heavy-duty engines, but called on the Agency to go further in lowering sulfur content in diesel fuel.

According to automakers, near-zero sulfur fuels are needed to enable the introduction of even cleaner, more fuel-efficient technology.

"Getting the sulfur out of diesel fuel will dramatically improve air quality, and it will enable us to develop a new generation of clean, light-duty diesel vehicles that are more fuel-efficient. These clean diesel vehicles are coming soon, and we need clean diesel fuel to run them," said Josephine S. Cooper, President and CEO, Alliance for Automobile Manufacturers.

"Clean diesel" refers to vehicles with diesel engines using clean diesel fuel together with emission control systems to reduce substantially emissions of particulate matter, nitrogen oxides and other pollutants.

At today's hearing, EPA is seeking public comment on its heavy-duty vehicle rule, which includes reducing sulfur in diesel fuel. The rule was proposed on May 17, 2000 and is expected to be finalized by the end of the year.

Under EPA's proposal, refiners must reduce the sulfur in diesel fuel by 97 percent over the next six years, and this cleaner fuel must contain no more than 15 parts per million (ppm) of sulfur. EPA's proposal also calls on manufacturers to achieve a 95 percent reduction in nitrogen oxide (NOx) emissions phased in during 2007-2010, along with a 90 percent reduction in particulate matter (PM).

EPA has stated that under its proposed plan, " ... diesel vehicles would achieve gasoline-like exhaust emission levels, in addition to their inherent advantages over gasoline vehicles with respect to fuel economy, lower greenhouse gas emissions and lower evaporative hydrocarbon emissions."

"Alliance members have made the call for low sulfur fuels a crusade because we need clean fuels to run clean vehicles," said Cooper. Due to the high sulfur content of diesel fuel, vehicles with heavy-duty engines, such as trucks and buses, have not been able to use state-of-the-art emission control technology.

In addition, low sulfur diesel fuel would provide immediate clean air benefits when used by the millions of trucks and buses already on U.S. roads. (For more information visit

The Alliance is supporting elements of EPA's proposed rule, but calls on the Agency to go further. EPA has proposed to cap sulfur in diesel fuel at 15 ppm by mid-2006, but manufacturers want near-zero sulfur content -- 5 ppm, along with improvements in other fuel parameters as recommended by the automakers' World-Wide Fuel Charter.

This ultra-clean fuel enables manufacturers to introduce advanced aftertreatment devices. Recent reports from the Department of Energy's Diesel Emission Control Sulfur Effects (DESCE) Program underscore the critical need for ultra-low sulfur by showing that even a few parts-per-million of sulfur greatly impair vehicle exhaust aftertreatment systems.

EPA also needs to adopt clean diesel fuel to continue fostering the development of and ready access to advanced diesel engine technology and hybrid propulsion systems that greatly increase fuel efficiency.

"Achieving the nation's dual goals of clean and energy-efficient transportation over the next decade will be considerably more difficult and expensive without clean diesel fuel," said Cooper. "Clean diesel technology, in particular, shows great promise as a scientific and engineering breakthrough. With clean diesel, we could greatly improve fuel efficiency, reduce fuel consumption and reduce emissions."

In Europe, where fuel can cost three times what it does in the U.S., 30-35 percent of the vehicles are diesel. Germany is already moving toward ultra-low sulfur content in fuels through incentives.

The Alliance of Automobile Manufacturers is a coalition of 13 car and light truck manufacturers. Member companies are BMW Group, DaimlerChrysler, Fiat, Ford Motor Company, General Motors, Isuzu, Mazda, Mitsubishi Motors, Nissan, Porsche, Toyota, Volkswagen and Volvo. Alliance member companies have approximately 600,000 employees in the United States, with more than 250 facilities in 35 states. Alliance members represent more than 90 percent of U.S. vehicle sales. For more information, visit the Alliance Web site at