As part of a “boot camp,” almost 1,000 International dealers had the chance to test-drive Navistar's new MaxxForce 15 diesel installed in two ProStar+ tractors. Developed in just two years from Caterpillar's discontinued C15 engine, the new 15L fills out the top end of Navistar's proprietary engine family. It is the only line of diesels not using selective catalytic reduction (SCR) to meet EPA 2010 emissions requirements.
Divided into seven waves of two-day sessions at Miller Motor Sports Park in Salt Lake City, UT, the dealers also spent time comparing torn down diesels from all of Navistar's competitors with the company's main big bore engine, the 13L MaxxForce 13.
While Navistar believes that 13L diesels will displace 15L engines as the dominant power plant for over-the-road Class 8 tractors, “the 15L will still have a place where customers need more than 500 hp.,” said Tim Shick, director of engine sales and marketing.
The new MaxxForce uses the block, oil pan, crankshaft, connecting rods and head castings from the C15, which Cat stopped selling in the U.S. truck market at the end of 2009. Navistar engineers adapted the MaxxForce 13 common rail fuel system, air system, twin turbos and “Advanced EGR” system.
Calling the engine “heavy and capable,” Shick said it weighs more than any other 15L on the market, but that extra weight is offset by not requiring a 400 to 500 lb. SCR aftertreatment system. Dealers are currently taking orders for ProStar+ and vocational PayStar models with the MaxxForce 15 with ratings ranging from 450 to 500 hp. and peak torques between 1,550 and 1,750 lbs.-ft. The severe-duty International 9900 will be available with ratings up to 550 hp./1,850 lbs.-ft in December, according to Shick.
LoneStar tractors will get the new 15L next year, as well as a 500-hp. version of the MaxxForce 13, Shick said.
Fuel economy for the engine “is within a couple of tenths of the MaxxForce 13,” which is “6.5 mpg for a ProStar with full aerodynamics and loaded to 80,000 lbs.,” Shick said.