Today’s heavy-duty diesel engine evolution has settled on two basic displacement configurations: 13-liter and 15-liter, the larger of which led North American sales for many years. Lately, however, 13-liter engines have emerged as the overall market leader.
The 13-liter shift?
“We’ve been doing a lot of research on these engines lately, and we are seeing a shift away from 15-liter engines to 13 liters,” Kevin Baney, chief engineer for Kenworth Trucks told the Commercial Carrier Journal. More line-haul customers are switching because of weight reduction and fuel economy benefits he added. “With our Paccar 13-liter MX engines today, we can offer them 385 horsepower all the way up to our 500-horsepower Cummins option, which will debut in January,” he says. “Our broad horsepower range works for most customers.”
Navistar saw the trend toward 13-liter power coming some years ago as customers became more focused on weight, payload and fuel efficiency, which Steve Gilligan, vice president of vocational and product marketing, drove the company in development of its MaxxForce 13.
“The added weight of emissions-related equipment and fluid is offset by the 13-liter engine,” ” Gilligan said.
Jennifer Rumsey, executive director of heavy-duty engineering for Cummins, notes that most of today’s 13-liter engines actually are 12- to 13-liter engines. While engines in this class have displacements ranging from 11.9 to 13 liters, 13-liter and 15-liter displacements fill different needs within the Class 8 truck market, she says.
