Fleet Management News & Business Info | Commercial Carrier Journal
Issue link: http://read.dmtmag.com/i/319866
COMMERCIAL CARRIER JOURNAL | JUNE 2014 61 The give-and-take of LOW-ROLLING-RESISTANCE TIRES N o one's gotten around to reinventing pine-scented air fresheners yet, but otherwise it seems that virtually every component or system found on today's heavy-duty trucks is undergoing some sort of evolutionary change. Tires are no exception. For profit-minded fleets, extending tire life always has been a priority. However, an increasing focus on fuel economy means that spec'ing tires simply for longer mileage no longer cuts it. Today, low-rolling-resistance tires have become a prime tool in a fleet's fuel-econ - omy arsenal, and the results have been encouraging. Doug Jones, customer engineering support manager for Michelin, says low-rolling-resistance truck tires can contribute as much as 20 percent toward a vehicle's fuel consumption performance. But truck spec'ing often is a game of give-and-take. At first glance, it's a given that low-rolling-resistance tires deliver superior fuel economy performance. But does that performance come at the cost of tire dura - bility and longevity? Fuel-efficient tire science Three main factors impact a tire's rolling resistance: tread compounding, tread pat- tern design and tire structure. "Tests show over 50 percent of the rolling resistance of a tire is generated from the tread and belt package," says William Estupinan, vice president of technical service for Giti Tire USA. Tire manufacturers develop tread com - pounding techniques to reduce the energy absorption and consequent heat generation within the tread and belt package while not compromising other important factors such as durability. These low-energy-absorbing materials sometimes are referred to as "reduced hysteresis" materials. "The tread pattern design is also an important consideration when trying to improve the fuel efficiency of a tire," says Estupinan, who lists other critical factors: streamlined ribs, blocks and lugs; a good balance between the cap and base compounds; a shallower tread depth; and a stiffer belt package. The dynamics of rolling resistance allow tire manufacturers to deliver greater fuel economy gains for truck fleets. "Like air The tread pattern design is also an important consideration. – William Estupinan, vice president of technical service, Giti Tire USA Pomona, Calif.-based KKW Transportation runs with Yokohama Tire's Zenvironment low-rolling-resistance tires. BY JACK ROBERTS No one questions their fuel economy benefit, but do fleets pay a longevity penalty for it?