Unlike its competitors in the heavy-duty on-road space, Navistar relied on advanced EGR technology for 2010 compliance instead of SCR, as did the others. Navistar touted the advanced EGR approach as being more cost-effective than SCR. The company was also vocal in its opposition to the use of SCR for compliance (“a license to pollute”), having argued that there was no operational mechanism to forestall cheating with SCR systems when urea is not present.

However, EPA 2010 regulations call for 0.20 g/bhp-hr NO_x; engine-out NO_x for the MAXXFORCE 13, as an example, was 0.35 g/bhp-hr.

New heavy-duty engines entering the market must obtain a certificate of conformity from EPA demonstrating that the vehicle or engine complies with the applicable emission standard(s). However, concerned that some manufacturers of heavy-duty engines might be forced out of the marketplace if they are unable to meet these standards, Congress required EPA to grant such manufacturers a certificate of conformity if they pay a non-conformance penalty (NCP). EPA also had established an “averaging, banking and trading program” for engine credits as another way to meet emission standards besides payment of NCPs.

In October 2011, Navistar informed EPA that it would run out of engine credits (used to meet emissions standards for non-compliant technology) in 2012. Given the imminent credit shortage, EPA estimated that it might have as little as 3-4 months to establish penalties before Navistar ran out of credits and would be unable to introduce any heavy-duty engines into commerce subsequent to that. EPA therefore established an NCP for Navistar, and invoked an exception under the Administrative Procedure Act (APA) that would have allowed it to dispense with otherwise applicable notice and comment procedures.

Navistar competitors—who had developed SCR solutions—filed suit against the EPA, arguing that the agency was giving preferential treatment to Navistar and that the NCPs were too low. The Court of Appeals agreed with the competitors, and in the June decision, vacated the EPA rule.

Navistar began its Class 8 SCR transition in December of 2012 with the on-time launch of the International ProStar with Cummins ISX15 and then the International ProStar with MaxxForce 13 with SCR in April. Today, the company’s portfolio of SCR-based heavy-duty trucks also includes the International PayStar 5900 Set-Back Axle and International 9900i with the Cummins ISX15 engine as well as the International PayStar, TranStar, and WorkStar with the MaxxForce 13 engine with SCR.

Navistar announced in early September that it has received more than 11,500 orders for Cummins ISX engines since 1 December 2012, and more than 6,000 orders for MaxxForce 13 engines with SCR since 1 March 2013.