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Tires

Low-rolling resistance tires can save fuel

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Low-rolling resistance tires are marketed as an easy way to save fuel—and money. But how much do they really save you? In collaboration with the University of Michigan—which ran the calculations based on Consumer Reports data—we have proof that low-rolling resistance tires could save $78 a year in fuel.

To run the calculations, the university used Consumer Reports rolling-resistance data from 49 all-season tires. The analysis covered T-speed-rated all-season tires, and H- and V-speed-rated performance all-season tires. T-speed-rated tires come in sizes to fit many cars and minivans. They are designed to handle most weather conditions, and emphasize comfort, quietness, and long tread life. Performance all-season tires are typically original equipment on new cars, and they are generally a step-up in handling but may trade-off some tread life and winter grip.

The data was collected at an outside lab where the resistance force to roll a tire under load at speed on a dynamometer was measured. The lower the rolling-resistance force, the more fuel efficient a tire is likely to be. Aside from Consumer Reports tire ratings, shoppers would be hard pressed to find such fuel efficiency information.

In general, if you wanted a low-rolling resistance tire, check our ratings, as we’ve found performance can vary. Should you choose not to confer with the ratings, your best bet is to buy an original equipment tire, as those are typically designed with good fuel efficiency as a high priority. Other replacement tires may trade-off some fuel efficiency for better wet grip and longer tread life. It’s worth mentioning there are a few replacement tires available touting good fuel efficiency, but they’re not commonplace.  

Traction Points From the Rolling-Resistance Report

There is a large overlap in rolling resistance between the all-season and performance all-season tires, meaning there are good choices for potentially low-rolling-resistance tires in each of the T-, H-, and V-speed-rated categories.

Rolling resistance data was used to predict fuel economy differences using industry guidance that a 10 percent change in rolling resistance may result in a 1-2 percent change in fuel economy. It was calculated that the average fuel consumption for cars on the road today is 21.6 mpg, as computed from a vehicle fleet average.

  • Based on those calculations, the potential fuel economy could rise from 20.9 mpg to 22.2 mpg when driving on tires with the highest rolling resistance versus the lowest.
  • Based on an average distance driven in a year of 11,346 miles, 32 gallons of fuel a year could be saved by going from the highest to lowest rolling-resistance tire.
  • At the time of the analysis, a cost savings of $78 was realized by going from a tire with the highest to lowest rolling resistance, based on the average price of a gallon of regular gas being $2.43.  

The estimates used in the report are similar to results Consumer Reports has found in actual on-vehicle fuel economy tests showing a 1-2 mpg difference when swapping between relatively high- and low-rolling-resistance all-season tires on our test car.

The study shows that you wouldn’t reap a windfall of savings by switching to low-rolling-resistance tires, but every little bit helps. We recommend when considering a tire purchase, look for a tire with good braking, handling, and hydroplaning resistance. After that look for tires that perform well in other areas important to you, such as comfort, winter grip, and tread life, and then consider rolling resistance as a tie-breaker.

Finally, keep your tires properly inflated. Underinflated tires raise a tire’s rolling resistance. A 0.3-percent drop in fuel mileage is possible for every 1 psi drop in tire pressure according to government estimates.  


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