Since the first installation of a PACCAR MX-11 engine into a Peterbilt truck earlier this year, the lightweight, fuel-efficient engine has been exceeding the company’s expectations, and those of its customers, Peterbilt Motors Company announced during the ATA Management Conference & Exhibition in Las Vegas.

“Feedback is overwhelmingly positive with customers noting improved fuel economy, outstanding reliability and exceptional performance,” said Darrin Siver, Peterbilt General Manager and PACCAR Vice President. “The PACCAR MX-11 engine has been a great addition to our truck lineup, a combination of industry-leading quality, value and overall return.”

He added that praise has come from customers in a wide range of applications, including regional haul, tanker, refuse, bulk haul and construction. The 10.8-liter PACCAR MX-11 engine is offered in Peterbilt Models 579, 567, 520 and 320.

Oak Harbor Freight Lines is an Auburn, Wash.-based LTL specialist that was one of the first companies to operate the engine, running it in three Model 579s. In addition to out-performing the carrier’s 400 unit line-haul fleet in fuel economy, the engines provided ample power to haul through the steep grades of the western terrain.

Accustomed to spec’ing larger-block engines, Oak Harbor Freight Lines Director of Maintenance Dan Vander Pol was skeptical at first.

“We didn’t expect to put them into full-time usage so quickly, but now we really rely on them to do their jobs,” said Vander Pol. “And we had actually planned on keeping them only on Portland runs, where they wouldn’t go into the mountains. But now we’ve got two of them going over Snoqualmie Pass every night. That’s a pretty good haul.”

He added it was well received by drivers. “I spoke to every driver who’s driven it and they all told me it pulls just fine,” he said.

H.R. Ewell, a food-grade tanker fleet serving the food industry throughout Canada, Mexico and the U.S., has more than 25 Model 579s equipped with PACCAR MX-11 engines. The carrier’s Fleet Maintenance Manager Scott Ewell recently attended a PACCAR MX-11 engine VIP event hosted by Peterbilt.

“We are running the MX-11 in new Peterbilt tractors pulling tankers at 80,000 lbs.,” said Ewell of the Lancaster County, Penn.-based company. “Our driver’s like the Peterbilts, they pull well and we are getting mid- to upper-7 miles per gallon. They are out performing other trucks in our fleet.”

About the PACCAR MX-11 Engine:
The PACCAR MX-11 engine has an output of up to 430 horsepower and 1,550 lb.-ft. of torque. It is produced at the state-of-the-art PACCAR engine manufacturing facility in Columbus, Miss., where the PACCAR MX-13 engine is produced.

PACCAR launched the MX-11 engine in Europe in 2013 and has manufactured and installed over 10,000 of the engines in vehicles built by its DAF Trucks division. PACCAR has over 50 years of engine development and manufacturing expertise.

The PACCAR MX-11 engine has six inline cylinders and a double overhead camshaft design. PACCAR MX engines are the only commercial diesel engines to use Compacted Graphite Iron (CGI) in both the engine block and cylinder head. CGI is approximately 20 percent lighter and 75 percent stronger than traditional gray iron. The PACCAR MX-11 engine is designed to achieve an industry-leading B10 life of one million miles. It also utilizes a common rail fuel system with injection pressures of 2,500 bar to optimize combustion for low fuel consumption and noise levels.