What are Low Rolling Resistance Tires?

Low rolling resistance tires are often touted as being very helpful when you want to help conserve fuel. By some estimates, up to 6% of your fuel bill could go away if you have low rolling resistance tires.

But what are low rolling resistance tires and how can you find them next time you want to replace your tires?

What are Low Rolling Resistance Tires?

First, the definition: Low rolling resistance tires are just what you think they are. They provide less resistance (less friction) when rolling along than other tires do. In other words, how easily do they roll down the road? Energy is continually being wasted through heat between the tire and the road, within the tire and between the tire and the rim.

Keep in mind that rolling resistance is not the same as grip, or how well a tire 'handles' the road. Although the two can be related, it is not a one to one relationship and you don't necessarily have to lose the grip to improve your rolling resistance.

As a simple rule, the harder a tire is, the less rolling resistance it will have. Which is why making sure your tires are properly inflated is so important. No matter what type of tire you have, the best thing you can do for fuel economy today is to check your tire pressure.

What kind of difference does resistance make? Although there is no hard and fast rule, a 10% reduction in tire rolling resistance should improve your fuel economy 1 to 2% (according to a study by the NREL). But the number varies widely by tire and vehicle type.

How is rolling resistance measured? The Society of Automotive Engineers measures rolling resistance by measuring the force needed to roll a tire against a dynamometer at a fixed speed of 50 mph (test procedure SAE J1269). SAE J2452 promises better results by measuring at different speeds, but SAE J1269 is the golden standard. Rolling resistance can typically vary 20 to 30% even among tires of similar size type and level of performance.

How does it affect me?

It is estimated that rolling resistance can account for 15% (stop and go driving) to 25% of a cars resistance to moving. So if a low rolling resistance tire improves your vehicles rolling resistance by 20%, your fuel mileage can be improved 3 to 5%.

Let's say you drive 15,000 miles a year at 20 mpg. That's 750 gallons a year. A 4% improvement means you save 30 gallons a year or $90 (at current fuel prices: $3). That's enough to justify paying extra for a low rolling resistance tire, as long as it's duration is the same as a similar tire, but with higher rolling resistance.

Green Seal choice for Low Rolling Resistance Tires

Green Seal has released another of their well-researched "Choose Green" reports, this time covering "Low Rolling Resistance Tires". The reports presents previously unpublished data on leading tires that have low rolling resistance. What is rolling resistance exactly?

It is a measurement of how easily the tire rolls down the road — minimizing the energy wasted as heat between the tire and the road, within the tire sidewall itself, and between the tire and the rim.

Green Seal found that rolling resistance differences of 20 to 30% are not uncommon among tires of an otherwise similar size, type, and level of performance. This means an individual vehicle could save up to 6% of its gasoline use if it were fitted with very efficient tires, paying for the additional cost in about one year. In words, a typical compact car such as a Ford Focus can improve its mileage from 30 mpg to 32 mpg simply by using lower rolling resistance tires. For a car averaging 15,000 miles per year the fuel savings is about $50 (at $1.50 per gallon).

Some of the tires which received top recommendations were: Bridgestone B381, Nokian NRT2 and Sumitomo HTR 200.