More Than a Quarter of Registered Trucks Equipped with Less Polluting Engines
More than 28% of all trucks registered in the United States are now equipped with advanced new technology clean diesel engines, according to new data compiled by R.L. Polk and Company for the Diesel Technology Forum.

More than 28% of all trucks registered in the United States are now equipped with advanced new technology clean diesel engines, according to new data compiled by R.L. Polk and Company for the Diesel Technology Forum.

The data includes registration information on Class 3-8 trucks from 2007 through 2012 in all 50 states and the District of Columbia.
Beginning in 2007, all heavy-duty diesel trucks sold had to meet particulate emissions levels of 0.01 grams per brake horse-power hour, a level near zero. Today 2.5 million of 8.6 million commercial trucks on the road, now have this technology, using either exhaust gas recirculation technology or catalytic reduction technology.
"The fact that more than 28% of all trucks on U.S. roads today are new technology diesel engines with near zero emissions is significant for the environment and the trucking industry," said Allen Schaeffer, the executive director of the Diesel Technology Forum.
Regionally, the Midwest has the highest percent of new diesel trucks, 31%, followed by the South at 29.8%, the Northeast at 29.1% and the West at 26%.
DTF says emissions from today's diesel trucks and buses are near zero due to more efficient engines, more effective emissions control technology and the nationwide availability of ultra-low sulfur diesel fuel.
“The new clean diesel technology has reduced emissions from heavy-duty diesel trucks and buses by 99% for nitrogen oxides and 98% for particulate emissions,” said Schaeffer.
He also noted that 2010 and later model trucks are experiencing an average of 3% to 5% improvement in fuel economy while new diesel technology and ultra-low sulfur diesel are benefitting many of the older diesel trucks built before 2007.
The Diesel Technology Forum is a non-profit national organization dedicated to raising awareness about diesel engines, fuel and technology.
More Fuel Smarts

Cummins Adjusts 2027 Engine Rollout After EPA Proposal
The engine maker will gradually introduce its new Model Year 2027 diesel engines while continuing to offer current models during the transition, citing the EPA's proposed emissions rule changes.
Read More →
EPA Proposal Could Ease 2027 Truck Costs and Buying Uncertainty
The proposal doesn't change the tougher NOx standard, but it would revise key implementation requirements that manufacturers say have driven up costs and complicated fleet purchasing decisions.
Read More →
Cummins, Paccar Ease DEF Derates After EPA Guidance
Updated diesel engine software gives truck operators more time to address emissions-system issues while staying compliant with EPA emissions standards.
Read More →
Maintenance in the Messy Middle Part 3: Biodiesel
Biodiesel can reduce emissions, improve fuel-system lubricity and use existing diesel infrastructure. But NACFE’s Messy Middle maintenance report says fleets must actively manage storage, cold-weather operation, filters and oil drain intervals to avoid problems.
Read More →
Enhance Fleet Performance with High-Efficiency Auxiliary Power Units
Drive sustainable cost savings while increasing driver comfort during short- and long-haul logistics operations.
Read More →
Maintenance in the ‘Messy Middle’ Part 2: Renewable Diesel Fuel
NACFE's latest Messy Middle Powertrain Service & Maintenance report says renewable diesel gives fleets an opportunity to reduce carbon emissions without changing trucks, fueling infrastructure or maintenance practices. But technicians still need to understand several important operational differences.
Read More →
The Diesel Engine Enters NACFE’s ‘Messy Middle’
NACFE’s new Messy Middle Powertrain Service & Maintenance report says keeping modern diesel engines running now depends as much on software, diagnostics and data as traditional mechanical service.
Read More →
DTNA Software Update Gives Truckers More Time Before DEF Derates Take Effect
The changes reflect EPA guidance aimed at reducing downtime caused by emissions-system faults while maintaining compliance requirements.
Read More →
New Agentic Predictive Maintenance Report Demonstrates How Degraded Aftertreatment Systems Waste Fuel
Questar analyzed a large mixed-class fleet and discovered it was wasting as much as $30 in fuel per vehicle, per day, because of mechanically degraded aftertreatment systems.
Read More →
New York City's Microhub Project is Delivering Results
Trucking, last-mile delivery companies, and environmental advocates like what they are seeing so far with New York's microhub program.
Read More →
