Peterbilt’s first lightweight Paccar MX-11 engine was installed recently in the company’s newest vocational truck, the Model 567, in a set-forward front axle configuration. The truck-and-engine combination was presented to Knife River, who drove it off the assembly line at Peterbilt’s Denton, Texas, manufacturing facility.

The 10.8-liter Paccar MX-11 engine has an output of up to 430 hp and 1,550 lb.-ft. of torque. It has six inline cylinders and a double overhead camshaft design. Paccar says its 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% lighter and 75% stronger than traditional gray iron.

The Paccar MX-11 engine is designed to achieve a B10 life of 1 million miles, meaning 90% of these engines should still be running at that mileage with few repairs.

It also uses a common rail fuel system with injection pressures of 2,500 bar to optimize combustion for low fuel consumption and noise levels, according to Peterbilt.

The truck will be used in Knife River’s mixer operations throughout the Northwest U.S., according to Peterbilt. 

Knife River was founded in 1917 and is based in Bismarck, N.D. It is a full-service civil and residential contractor operating in 19 states. In addition to its contracting services, Knife River is one of the U.S.’s largest aggregate producers and supplies asphalt, ready-mix concrete and other construction materials.

Peterbilt’s Model 567 SFFA is available in both 115- and 121-inch bumper-to-back-of-cab lengths. The 115-inch BBC has a bumper to front axle distance of 29 inches and the 121-inch BBC has a bumper to front axle distance of 31 inches. Peterbilt also offers the Model 567 in a set-back front axle configuration, also in a 115- or 121-inch BBC length.
The Model 567 SFFA Knife River was presented is one of 200 Peterbilt trucks the company has ordered, according to Peterbilt.