The MaxxForce15 is available in the International ProStar+ with up to 500 hp and 1,850 lb.-ft. of torque.

Navistar officials said the recent introduction of its 15-liter engine, its developments in alternative fuel engines, and growth in other areas have enabled the company to establish itself at a much broader level of industry leadership than five years ago.

“With the addition of our MaxxForce 15, our line-up of MaxxForce Advanced EGR big bore engines truly differentiates us from the competition,” said Jim Hebe, Navistar’s senior vice president, North American sales operations, during a trade event in Louisville, Ky. “The introduction of the ProStar+ with MaxxForce 15 now gives customers the ultimate combination in durability and power.”

Navistar is the only heavy-duty engine maker using exhaust gas recirculation without selective catalytic reduction to meet federal emissions regulations.

The MaxxForce15 for the International ProStar+ is available with up to 500 hp and 1,850 lb.-ft. of torque. International PayStar heavy-duty vocational trucks are available with MaxxForce 15 up to 550 hp.

Navistar also demonstrated a prototype 2011 International ProStar+ powered by a 13-liter MaxxForce dual fuel engine powered by diesel and liquefied natural gas.

In partnership with Clean Air Power Ltd., Navistar has built and tested the 122-inch BBC tractor with a 430-hp, 1,550 lb.-ft. engine that uses diesel pilot injection for combustion on the compression stroke and mixes air and LNG on the intake stroke. The result is an engine that runs on a mixture of 15 percent diesel and 85 percent natural gas, Hebe said.

The dual fuel MaxxForce engine includes minimal changes to the stock diesel engine other than the addition of a natural gas injection system. Changes to the chassis include the addition of a 26-inch diameter, 119-gallon standard LNG tank that provides a 400-mile range, a coolant heated fuel vaporizer, and an LNG regulator and filter.