In the U.S. Environmental Protection Agency’s SmartWayTransport Partnership’s specifications for Class 8 combination vehicles,lighter-weight tractor and trailer components are recommended as potential fuelsaving options. Reducing 3,000 lbs. from a heavy-duty vehicle, EPA notes, couldsave between 200 and 500 gallons of fuel each year.
“Truck fuel consumption increases with the weight of thevehicle,” EPA SmartWay programliterature states. “Heavier trucks require more fuel to accelerate and to climbhills and every ten percent drop in truck weight reduces fuel use between fiveand ten percent. Using aluminum and other lightweight components whereappropriate can reduce empty weight, improve fuel efficiency, and reducegreenhouse gas emissions.”
Most truck manufacturers, EPA goes on to note, offerlightweight models that are 1,000 or more lbs. lighter than comparableversions. Lighter-weight models combine different weight-saving wheel-endoptions that may include aluminum wheels. SmartWay specs also include arecommendation for using optional low rolling resistance wide base single tiresmounted on aluminum wheels.
Wide base wheels
In turn, wheel manufacturers are offering aluminum wheels in22.5x14-in. sizes to help bring additional weight and fuel savings to fleets.Alcoa notes that some fleets have experienced savings of 3% to 7% with widebase wheel and tire combinations. Estimates from Accuride include 2.5 % fuelsavings per tractor and 5% per combination vehicle.
Wide base wheel and tire assemblies save fuel, in part,because they include only half as many flexing sidewalls as a set of duals.Tire rolling resistance, a major factor in a tire’s fuel efficiency, is theamount of drag created by tires as the vehicle runs down the highway. Part ofrolling resistance comes from the flexing and un-flexing of the tire as itrolls into and out of contact with the pavement.
Actual weight savings with wide base aluminum wheels vary bymanufacturer. Alcoa’s 14-in. wide base aluminum wheels, according to thecompany, can save 318 lbs. per axle or 1,272 lbs. per combination when used inplace of dual wheels on drive and trailer positions. The wheels, which weighonly 68 lbs. each, are load rated up to 12,800 lbs.
Accuride DupleX-One wide-base 22.5x14-in. aluminum wheels,the company notes, reduce fuel expense or increase payload capacity when usedin place of traditional dual wheel sets on tandem-axle tractors and trailers.Developed in conjunction with Michelin, the forged aluminum wheels can save 120lbs. per axle.
Additional benefits of wide base single tires and wheels,the manufacturers also point out, include reduced maintenance costs. Thoseexpenses are lower, they say, because there are only four wheels per tandemcompared to eight. In addition, without an inner wheel, inflation and visualinspection becomes much easier and more effective. Wide base aluminum wheel...