Overdrive Magazine | Trucking Business News & Owner Operator Info
Issue link: https://read.dmtmag.com/i/101364
Balance of power The leading heavy-duty engine sizes differ by only two liters, and one now dominates the market. Make sure you're powered by the best fit for your operation. By Jack Roberts F or many years, competition in the diesel engine world was defined by size and power. At the height of the power wars, it wasn't unusual to see a long-nosed 600-horsepower tractor turning 1,900 rpm and running 75 mph without breaking a sweat. In today's world of $4 diesel, spec'ing a 600-horsepower engine demands a business case in which the requirement for power and torque is an absolute necessity – usually heavyhaul or some vocational applications. Otherwise, it can be a vanity purchase for those with money to burn. Meanwhile, today's technology has enabled both 13-liter and 15-liter engines to deliver relatively high horsepower and torque while turning in fuel economy numbers unachievable a decade ago. Why 13-liter engines rule the market The trend toward bigger engines peaked around 2008 or 2009. Among Overdrive readers polled in 2008, those with model year 1995 or older trucks had engines averaging 12.7 liters. Those with 2001 or newer trucks had engines averaging 13.9 liters. Late 2008 saw diesel prices' worst spike ever, and the industry has been more fuel-sensitive ever since. Since then, more of Kenworth's line-haul customers are switching to 13 liters because of weight reduction and fuel economy, says Kevin Baney, chief engineer for Kenworth Trucks. "With our Paccar 13-liter MX engines today, we can offer them 385 horsepower all the way up The 12.9 liter PACCAR MX-13 engine has power ratings from 385 to 500 horsepower. It is standard in Peterbilt and Kenworth on-highway and vocational trucks. A Cummins ISX15 for higher horsepower (with up to 600 horsepower) applications is available as an option. to our 600-horsepower Cummins option, which will debut in January," he says. Navistar saw the trend toward 13-liter power coming some years ago as customers became more focused on weight, payload and fuel efficiency, says Steve Gilligan, vice president of vocational and product marketing. "That's what 22 | Overdrive | January 2013 Cover_Story_0113.indd 22 1/14/13 6:09 PM