The NHTSA announced on Friday that they are proposing a new rule that would place stiffer regulations on medium and heavy-duty truck emissions by 1 billion metric tons. This new regulation is aimed at reducing fuel costs by about $170 billion by next decade.
http://www.freep.com/story/money/2015/06/19/environmental-protection-agency-heavy-trucks-greenhouse-gases/28976747/The U.S. Environmental Protection Agency and the National Highway Traffic Safety Administration (NHTSA) established the standards that will now face a period during which industry and environment groups will comment. The standards could be revised.
The agencies are asking for a cut in carbon emissions between 2021 and 2027 that would be nearly equal to the greenhouse gas emissions from all U.S. residences in one year. The fuel-efficiency targets would save more oil than what the U.S. currently imports annually from the Organization of Petroleum Exporting Countries.