Peterbilt has announced the availability of a new low nitrogen oxide (NOx) compliant Paccar MX-13 engine. The new engine is compliant with all California Air Resource Board (CARB) diesel emissions regulations. It will be offered in Peterbilt Model 579, Model 567 and Model 589 trucks.

Aftertreatment System Refinements

Peterbilt said the new MX-13 version meets the CARB Omnibus Regulation and features redesigns of internal hardware and the aftertreatment system to effectively reduce NOx emissions.

The larger volume aftertreatment system includes a compact twin assembly featuring a 48-volt generator located in the flywheel housing, and an electrical heater located in the inlet. These upgrades provide lower NOx output.

Peterbilt said the internal hardware now features a larger volume mixer, longer selective catalytic converter (SCR) and an improved and more durable NOx sensor design with increased longevity for improved uptime. These features allow Peterbilt customers to achieve increased engine efficiency and fuel economy while continuing to meet stringent CARB emissions regulations.

The CARB low NOx compliant Paccar MX-13 engine combines proven diesel powertrain with next-generation emissions technology, according to Peterbilt.

Two Power Ratings

It is available in two ratings with a flat torque curve providing performance across a wider range of RPMs for excellent drivability and fuel economy. This includes a high performance 510-horsepower rating with 1,850 lb.-ft. of torque and an efficiency focused rating of 455-horsepower and 1,650 lb.-ft. of torque between 900 and 1,325 RPM.

“Paccar MX engines were engineered for reliability and fuel economy in a comfortable, quiet and powerful package. The new CARB low NOx Paccar MX-13 engine offers the same great features with a reduced carbon footprint for our customers,” said Scott Newhouse, Peterbilt chief engineer.

Peterbilt Models 579, 567 and 589 with the CARB low NOx compliant Paccar MX-13 engine are available for orders now.