FleetMag.com |

Paccar has introduced the Paccar MX engine to be installed in heavy duty North American Kenworth and Peterbilt trucks beginning this summer. The engine, developed through a very significant investment in research and testing, has been designed to deliver industry leading performance, durability and reliability, along with excellent fuel efficiency.

The engine will work with all types of transmissions and is available with a horsepower range of 380 to 485 horsepower and torque outputs from 1,450 to 1,750 pound-feet.

That is the sweet spot of the Class 8 industry, notes Alan Treasure, Paccar’s director of marketing, covering about 65 percent of the trucks used in both over-the-road linehaul and vocational applications.

“This power range, combined with excellent fuel efficiency, high reliability, durability, lightweight design and low cost of ownership makes it an ideal choice for these truck users,” Jim Cardillo, Paccar president, adds.

“The Paccar MX is designed to meet the U.S. Environmental Protection Agency’s 2010 emissions regulations and has accumulated over 50 million test miles in rigorous and severe conditions in North America,” he says. EPA certification is expected soon.

The Paccar MX engine uses selective catalytic reduction (SCR) in combination with exhaust gas recirculation (EGR) to meet the emissions regulations.

For the SCR catalyst, it is using copper zeolite, Craig Brewster, Paccar assistant vice president, says. Copper zeolite is much more efficient in reducing diesel engine emissions (about a 32 percent improvement) compared to the iron zeolite commonly used, removing nitrogen oxides emissions across a broad temperature range, and this helps better fuel economy.