Copyright Bloomberg via Getty Images

A Third of U.S. Diesel Truck Fleet is Near-Zero-Emission

July 3, 2014
95 percent of all heavy duty trucks in the U.S. are diesel-powered.

More than 2.9 million of the 8.8 million medium and heavy duty commercial trucks registered in the United States are now equipped with newer technology clean diesel engines, according to new data compiled by HIS Automotive for the Diesel Technology Forum (DTF). Beginning in 2007, all heavy duty diesel trucks sold had to meet particulate emissions levels of no more than 0.01 grams per brake horse-power hour (g/HP-hr)—a level near zero. 

“Because more than 95 percent of all heavy duty trucks are diesel-powered it is significant that more than one-third of these trucks are near zero emission vehicles,” said Allen Schaeffer, the executive director of the Diesel Technology Forum.  “Diesel trucks are literally the driving force behind goods movement in the U.S. and worldwide economies so the fact that the clean diesel fleet is increasing is good news for improved fuel efficiency and the environment. These new trucks are so clean that it now takes more than 60 of today’s clean diesel trucks to equal the emissions from a single 1988 truck. 

“Last year was the fifth consecutive year of increased penetration of the new clean diesel trucks in the fleet, reflecting the continuing confidence that American truckers have in the performance and fuel efficiency improvements of new technology diesel engines,” Schaeffer said.

In December 2000, EPA adopted a rulemaking to establish stringent standards designed to reduce emissions from on-road heavy-duty trucks and buses by up to 95 percent and to cut the allowable levels of sulfur in diesel fuel by 97 percent. 

Under the Environmental Protection Agency’s 2007/2010 heavy-duty engine and highway diesel fuel sulfur control requirements, beginning with the 2007 model year, 100 percent of the new on-road diesel trucks were required to meet the near zero particulate emissions standards and 50 percent were required to meet the lower NOx exhaust standards.  Beginning with the 2010 model year, 100 percent of the new on-road heavy-duty diesel engines were required to meet the NOx exhaust standards. 

In addition, a sulfur cap of 15 parts per million (ppm) was instituted beginning June 1, 2006 for 80 percent of the diesel fuel sold by major refiners for use in highway vehicles.  The 15 ppm sulfur cap was increased to 100 percent after December 31, 2010. 

U.S. Clean Diesel Truck Growth by Year









Percentage New Diesel Trucks








Percentage Annual Increase








(Source: IHS Automotive, June 2014 for the Diesel Technology Forum)

Latest from Transportation & Distribution

176927300 © Welcomia |
96378710 © Nattapong Boonchuenchom |