WARRENVILLE, Ill. – Navistar International is inching closer to the EPA's 2010 0.20g NOx limit for its 2011 model year MaxxForce DT mid-range diesel.

The truckmaker announced that it has received certification from the EPA for the MaxxForce DT at 0.39 g/bHpHr NOx using Navistar’s EGR emissions solution.

The company says the certification represents a 22 percent emissions reduction from the original 0.50g certification and demonstrates progress to achieving the 0.20g standard.

"Our product development team has been laser-focused on our 0.20g NOx in-cylinder emissions solution for the past four years," said Ramin Younessi, group vice president, product development and business strategy. "Getting to 0.2g NOx through our in-cylinder technologies has always been part of our plan and remains so today."

Navistar also has received EPA and the California Air Resources Board (CARB) certification for the 2011 MaxxForce 15 big bore diesel (which will be available in 2011 International ProStar Plus units) and recently submitted its MaxxForce 13 at 0.20g NOx for EPA certification.

The company intends to phase-in its engines in the years ahead in an effort to "make emissions compliance as seamless as possible" for customers.

Navistar is able to do this because it has amassed credits from the EPA for producing smaller engines that were cleaner than their required emissions standard.

Although the company has 0.20g-compliant 13- and 15-liter engines at the ready, Navistar VP of marketing Jim Hebe told us at the Mid America Trucking Show that Navistar doesn't intend to run them until it runs out of credits "because there's a lot of technology we want to add to them until we get to that point."