Proposed standards for medium- and heavy-duty vehicles would reduce diesel consumption

Proposed fuel economy and greenhouse gas emissions standards would increase fuel economy and reduce diesel consumption in medium- and heavy-duty vehicles. The first phase of medium- and heavy-duty vehicle standards was recently implemented, starting with model year 2014. The proposed Phase 2 standards would take effect in model year 2021 for most medium- and heavy-duty vehicle classes and increase in stringency through model year 2027. More »