Kenworth has introduced a California Air Resources Board (CARB) compliant version of the Paccar MX-13 engine. The engine is available as a spec for heavy-duty Kenworth models that meet 2024 requirements.

The new Paccar MX-13 CARB-compliant engine is available to order now on select Class 8 models, including the T680, T880 and W990.

Production will begin in the fourth quarter of 2024.

 A New Aftertreatment System

According to Kenworth, the Paccar MX-13 CARB-compliant engine features new aftertreatment hardware that meets stringent California low nitrogen oxide (NOx) emissions requirements.

To meet the more stringent CARB emissions requirements, the MX-13 CARB engine utilizes a twin-canister selective catalytic reduction (SCR) aftertreatment along with more optimized emissions controls systems while continuing to provide excellent reliability, performance, and efficiency.

“Our customers are looking for better options to successfully navigate the complexities of the evolving regulatory landscape,” said Kevin Haygood, Kenworth assistant general manager for sales and marketing. “Kenworth models equipped with Paccar’s MX-13 CARB-compliant engine achieve compliance with stringent emissions regulations while also delivering a solution that drives increased engine efficiency and enhanced fuel economy,”

The Paccar CARB-compliant MX-13 engine is available in two options: a 510-horsepower rating with 1,850 lb.-ft of torque and a 455-horsepower rating with 1,650 lb.-ft of torque.

Both ratings deliver performance and drivability without compromise on fuel economy, according to Kenworth. Together with the Paccar TX transmissions, and Paccar DX rear axles, the MX-13 CARB-compliant engine gives fleets an efficient and integrated low-NOx solution, the OEM said.