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July 17, 2014   |   Diesel Technology Forum

Press Release

Diesel Technology Forum Statement on “Rolling Coal”

Contact: Steve Hansen (301) 668-7230 shansen@dieselforum.org

Washington, D.C. – The Diesel Technology Forum today issued the following statement regarding the practice known as “Rolling Coal”, whereby a diesel pickup truck engine and/or emissions control system is modified to generate excessive black smoke emissions.

“The diesel industry is extremely disappointed that a small segment of diesel pickup truck owners have chosen to tamper with the emissions and engine control systems to over-fuel the engine so as to deliberately produce black smoke emissions. For the last decade, the industry has invested billions of dollars to produce diesel engines that today are near-zero in emissions. That’s why they’re called clean diesel,” said Allen Schaeffer, the Executive Director of the Diesel Technology Forum, a non-profit educational group.

“Diesel engines have long been a popular option in heavy-duty pickup trucks because of their superior fuel efficiency and towing performance - not black smoke emissions. This practice of ‘rolling coal’ which has targeted drivers of hybrid vehicles, pedestrians, bicyclists, law enforcement and others is dangerous, harmful to the environment, and illegal. We urge state and local air quality and law enforcement officials to fully enforce all clean air and vehicle emission laws available to stop this unlawful practice.

Clean Diesel: All of the Power, None of the Smoke

“We’re proud to be ‘rolling clean’ with today’s new clean diesel pick-up trucks, which utilize advanced combustion and emissions control technology to meet the most stringent of Environmental Protection Agency (EPA) clean air standards. As a result, these clean diesel trucks have near zero emissions of particulate matter as well as other emissions.

“Since 2007, engines have been designed to run on ultra-low sulfur diesel fuel that has reduced sulfur content from 500 part per million (ppm) to 15 ppm – a 97 percent reduction. This lower sulfur fuel has enabled manufacturers to reduce emissions through use of emissions control technologies such as particulate filters.

“The Diesel Technology Forum is strongly opposed to tampering with emissions controls or engine performance for the purpose of generating excess smoke emissions - both of which are in violation of the Clean Air Act. Highly modified vehicles creating black smoke by over-fueling are not representative of mainstream diesel owners or vehicles, and certainly do not represent the new generation of clean diesel technology.

Billions of Dollars of Research & Development Have Resulted In Clean Diesel Technology

“The diesel engine, filter and equipment manufacturers worked closely with EPA, the California Air Resources Board, national health and environmental organizations and numerous other organizations over the years to develop today’s clean diesel technology.

“This research and development has lead to the creation of the world’s cleanest diesel engines and fuel which has reduced particulate matter and NOx emissions by more than 98 percent. In addition, the new technology has increased diesel fuel efficiency.

“According to research commissioned by the Diesel Technology Forum, a new diesel powered pickup truck will consume 425 less gallons of fuel in one year compared to a comparable gasoline powered pick-up. A typical diesel pickup truck owner will save, on average, $1,400 in fuel costs thanks to the efficiency of these clean diesel engines. This is a significant savings that will be compounded each year of ownership.

“Tampering with emissions control systems to purposely create higher emissions and smoke is completely contrary to this effort. It’s bad for the environment, a complete waste of fuel and may invalidate manufacturer’s warranties. The superior fuel economy of these clean diesel vehicles helps promote energy independence, but only when the engine and emissions systems are operating as designed. Over fueling is wrong and the practice needs to stop.”


The Diesel Technology Forum is a non-profit national organization dedicated to raising awareness about the importance of diesel engines, fuel and technology, and working with policymakers and other stakeholders on common solutions. Forum members are leaders in clean diesel technology. For more information visit www.dieselforum.org.

For the latest insights and information from the leaders in clean diesel technology, join us on Facebook, follow us on Twitter @DieselTechForum, or YouTube @DieselTechForum and connect with us on LinkedIn.

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Media Inquiries:
Allen Schaeffer
Executive Director
(301) 668-7230

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