According to a new study by the University of Michigan Transportation Research Institute, switching to low rolling resistance tires can save an average of $150 a year for drivers.
UMTRI research professor Michael Sivak examined rolling resistance for 63 new, same-sized tire models. Each tire had the same load and inflation pressure in order to calculate the fuel consumed annually by the average driver. The tires used represented a cross-section of current T-, H- and V- speed-rated tires. He then calculated differences in fuel used (and money spent) between tires at the extremes of rolling resistance.
“One parameter on which tires differ is their rolling resistance—the force resisting the motion when an object rolls,” said Sivak. “Tires with low rolling resistance roll easier and, therefore, get better mileage than tires with high rolling resistance.“
The U.S. Transportation Research Board estimates that a 10 percent increase in tire rolling resistance will result in about a 1.5 percent decrease in vehicle fuel economy.
Rolling resistance (RRf) for the combined set of all tires examined ranged from 6.89 lbs. to 12.5 lbs., with a median of 10.28 lbs. For the average vehicle currently on the road, the rolling resistance extremes translate into a maximum fuel economy of 22.4 mpg (RRf at 6.89 lbs.) and a minimum of 20.7 mpg (RRf of 12.5 lbs.), with a median of 21.4 mpg (RRf at 10.28 lbs.).
“Consequently, the obtained rolling resistance extremes yield a minimum and maximum annual fuel consumption of 505 gallons and 547 gallons, respectively,” Sivak said. “At the average 2013 price of regular gasoline, the obtained fuel-consumption results in a $147 difference in the annual cost of gasoline per light-duty vehicle.”
For the combined set of all tires, the added fuel consumed with tires at the current maximum rolling resistance represents an 8.3 percent increase compared to the fuel consumed with tires at the current minimum rolling resistance.
Sivak’s study is the first comprehensive evaluation of how much fuel a driver can save when using tires with low rolling resistance.
If you have questions about rolling resistance or fuel-efficient tires, please contact your nearest Dunn Tire store.