CARB and EPA Low NOx Engines and Trucks Announced

Background

Both California (CARB) and the U.S. EPA have set stringent standards for limiting NOx emissions from heavy-duty trucks. We have covered these standards previously. Without going into the intricacies of the rules and the differences, it is important to point out that compared to today, California requires an intermediate 75% reduction of NOx starting model year (MY) 2024, while starting MY 2027, the final EPA tailpipe standards apply across the country and require a NOx reduction of 82.5% on existing FTP & RMC lab transient test cycles.