EPA and the U.S. Department of Transportation finalized new emission and fuel efficiency standards yeterday for “medium- and heavy-duty vehicles.”  These categories include not only 18-wheelers but also buses, vans, and large pickup trucks among others. According to EPA, the vehicles covered account for only 5% of road traffic but 20% of emissions and fuel use. The new rule will apply through 2027 and will begin to affect some trailers as soon as 2018. EPA’s official announcement, which you can read here touts the rule will lower CO2 by approximately 1.1 billion metric tons and result in savings in fuel costs for vehicle owners.