How to find fuel efficient LRR (low rolling resistance) tires

[theorist]

<div class='quotetop'>QUOTE(grasshopper @ Jun 29 2006, 11:36 AM) [snapback]278598[/snapback]</div>

I have gotten an abundance of useful information from these posts and I think I have mass quantities of info to help me make my tire decision. However, how or where do I find the RR (rolling resistance) for all the tires mentioned here? Mileage is important to me and that is why I purchased a Prius. </span>
[/b]

I believe many of us are concerned about the rolling resistance of replacement tires and their effect on fuel consumption and emissions. While data on rolling resistance of different tires is very hard to come by, I've found some limited sources of data to complement the user reviews here at PriusChat.

The best single source I've found is a 2003 Green Seal report: http://www.greenseal.org/resources/reports...gresistance.pdf

Consumer Reports rated rolling resistance in their separate tests of standard all-season passenger tires (Nov 2005), high-performance all-season tires (Nov 2003), and touring-performance all-season tires (Nov 2002).

Very few manufacturers release any data or even claims. Continental claims that the ContiProContact successor to their LRR CH95 tire is even more rolling resistant. Michelin only refers to their Energy tires such as the MXV4, but Consumer Reports rates most Michelins' rolling resistance well. http://www.michelin.com/corporate/front/te...XE_RECH&lang=EN

Weight often correlates with rolling resistance. You can find the weight of nearly any tire at tirerack.com.

TireRack.com's survey doesn't address rolling resistance but their open ended user reviews often do. If you're want an idea of the rolling resistance of a particular tire, look for keywords like (fuel, economy, efficiency, mpg, lrr, rolling, resistance, mileage, gas, gallon) in the user reviews for your candidate tires. You can also find a tire review from a Prius driver and then search for all reviews of tires used on Priuses (or Insights, TDIs, Echos, Civics, Corollas) if you want to see what fuel efficiency oriented drivers thought of their tires.

Vehicle manufacturers are often criticized by some for giving too much weight to rolling resistance to boost EPA ratings. If you want a relatively low rolling resistance you're often safer with a tire that is OEM on many new cars, especially new cars trying to attract buyers with high EPA MPG numbers.

If I had considered these clues earlier, I wouldn't have bought the BF Goodrich Traction T/A (H) tires for our Elantra last year. The test results and survey data was accurate -- the traction is fabulous in nearly all conditions and the handling and treadwear are very good. I was surprised to lose 5-10% in fuel efficiency from the Michelin MXV4 Plus tires. In hindsight, if I'd been more careful I should have expected this. The Traction T/A weighs more than nearly all tires and much more than the Michelin Energy MXV4 Plus. The Traction TA is not OEM on any car that I know of, while the Energy MXV4 Plus is a common OEM tire. TireRack user reviews often complain of increased fuel consumption with the Traction TA and often brag about reduced fuel consumption with the MXV4.

For the Prius, I hoped for low rolling resistance of the ContiProContact based on OEM usage including on VW TDIs, Continental's claim that it was more fuel efficient than their Green Seal recommended EcoPlus CH95 (http://www.contionline.com/generator...tasheet_en.pdf), a remarkably low mass in the size I chose, and a maximum inflation pressure of 51 psi. I confirmed low rolling resistance of these tires more with a coast down test. I put the car in neutral at 40 mph and let it roll for a fixed 1.5 mile stretch of road and measured the speed at the end. Measured MPG also confirms lower rolling resistance than the Dunlops I was using.

Our task of considering rolling resistance (and effects on fuel consumption and emissions) will be easier when the California Energy Commission publishes it's own measurements of rolling resistance of over a hundred different tires in 2007 or 2008. http://www.energy.ca.gov/transportation/ti...ency/index.html

I'm really hoping that our DOT will wake up and require rolling resistance to be in the UTQG (Uniform Tire Quality Grade) that's on every tire, together with tread wear, wet braking, and heat resistance which are currently graded.

I hope readers find these sources useful. I look forward to hearing about other sources of data on rolling resistance.

<span style="color:#FF0000">Update:
I just found a fabulous report from the National Academies' Transportation Research board. This is by far the most comprehensive and trusted research report on fuel efficient tires and rolling resistance that I've found to date. This is a 110 page report from the National Academies. Don't worry. It has a has an executive summary, a detailed table of contents, and you can search to find what interests you.

Tires and Passenger Vehicle Fuel Economy: Informing Consumers, Improving Performance -- website

Report - pdf

Raw data on recent tires - pdf

[grasshopper]

Thanks theorist. I want to drive that VW!

[tnthub]

Rolling resistance will inherently be tied to the surface upon which it is tested. An asphalt country road will be different than a concrete highway or a drag strip. Tread designs, rubber compounds, inflation pressures, weight distribution, and driving styles will all play a part in how much rolling restance a tire will achieve and the environment, even whether or not it is winter or summer will also have a lot to do with it.

Remember, less resistance basically equates to less traction in most standard tires on most standard cars.

Our state recently attempted to ban the sale of tires that did not meet or exceed the rolling restance ratings of the stock OEM tires.

As much as i want to save fuel, the amount of actual savings was finally proven to be less than one tenth of one percent, and it was successfully argued that simplky promoting a program where drivers would keep their tires at the manufacturer recommended pressures would result in a greater overall savings.

I think this is a very dangerous path to go down. not in terms of value or in terms of providing information, but in uninformed politicians looking to gain votes by making false promises. The single greatest thing that anyone can do to improve fuel economy is to improve their driving habits and drive less. Tires are way down the list well after air filters, synthetic oils, spark plugs and wires, and simply building more efficient vehicles.

i understand you are probably far more educated than i in these matters but what maine tried to do was basically outlaw almost every aftermarket tire manufacturer from doing business in the state, except of course for state or municipal owned vehicles. In my state we have many hunters, fishermen, and often have lots of snow in the winter and plenty of mud in the spring... Thos pickup trucks with big tires would all be gone, and so would my camaro which has 28 x 12 1/2 x 15 inch rear tires which help raise the fuel economy of the vehicle over the stock 26 inch diameter tires...

[theorist]

<div class='quotetop'>QUOTE(tnthub @ Jun 29 2006, 03:40 PM) [snapback]278733[/snapback]</div>

As much as i want to save fuel, the amount of actual savings was finally proven to be less than one tenth of one percent...[/b]

Savings from regulation or from using LRR tires? Every report I've read estimates a potential 3 to 5% fuel savings between tires. If you have a source that differs drastically, I'd like to see it.

I think this is a very dangerous path to go down. not in terms of value or in terms of providing information, but in uninformed politicians looking to gain votes by making false promises. The single greatest thing that anyone can do to improve fuel economy is to improve their driving habits and drive less. Tires are way down the list well after air filters, synthetic oils, spark plugs and wires, and simply building more efficient vehicles.[/b]

I completely share your disgust with this misguided regulation. I'm upset that California has apparently already created a large database on rolling resistance of existing tires, but instead of sharing this information with the public so that consumers can make informed decisions to conserve fuel, they are keeping it private and instead using it to build a case for regulating consumer choice of replacement tires as you describe!

The fact that states are considering telling consumers that only state and municipal can use tires that consume as much as 10 gallons of gas a year more than the OEM tires, but the consumers are free to choose a large, heavy vehicle that consumes hundreds of gallons more than more efficient, affordable alternatives is ludicrous. Imagine that the EPA refused to share with consumers it's MPG estimates for cars (or trucks, no wait, no need to imagine there.) Imagine that the EPA instead used these secret estimates to simply tell consumers which cars they could and could not buy. As inane as this would be, it would make more sense than what's proposed with tires. I suppose vehicle manufacturers have more effective lobbies than tire manufacturers. On top of that most of us Americans don't fully appreciate the the safety importance of tire traction or the fact that heavier vehicles protect their occupants at the expense of greater injuries to occupants in other vehicles.

I believe that consumers should make more their own better informed choices. If our US government want's to reduce fuel consumption, we should do what every other industrialized country does -- tax it more. Of course we'll need to vote Halliburton and Exxon out of office before this happens.

[tnthub]

I will try to hunt down the source of the info. It may be partially biased as are many of these so called scientific surveys as many are privately funded. I believe the info was published by SEMA.

[DocVijay]

As someon else said, just keep in mind that most LRR tires are made that way throught he use of a harder rubber compound, and usually means less overall traction. The tire industry has yet to design a tire with excellent grip and low rolling resistance.

It's the same with those get 4 tires for $99 specials you see, or those tires that will last for 75,000 miles. THose things are rock hard so they don't wear down, but the loss in traction can be lethal.

Just use caution, as the 3-5% mileage gain won't mean a damn thing when that tire gives you a longer stopping distance.

Don't ever sacrifice economy for safety.

[theorist]

<div class='quotetop'>QUOTE(DocVijay @ Jun 29 2006, 06:00 PM) [snapback]278815[/snapback]</div>

The tire industry has yet to design a tire with excellent grip and low rolling resistance.
[/b]

While I don't want to debate the definition of excellent grip, I would like to point out that the Sumitomo HTR 200 is the Tire Rack's best surveyed high performance summer tire. It's also low rolling resistance, according to Green Seal. I've heard rumors that Yokohama's ultra high performance ES100 is also low rolling resistance. I believe Michelin's MXV4 and Continental's CH95 and ContiProContact touring tires provide respectable though not excellent levels of grip. These are OEM on Audis, BMWs, VW GTIs, and the like. I believe the Potenza RE92 is OEM in the Subaru WRX and Lexus IS350.

There certainly tradeoffs in tire design. We could as easily say than there isn't a tire with excellent grip and long treadwear, a smooth ride, good all season traction, or low noise. For me the challenge is that out of all of these criteria, data on rolling resistance is the hardest to find.

[Tideland Prius]

I will back the Michelin Energy MXV4 Plus. They came stock on our 02 Camry XLE and we replaced them with identical ones when the time came. They're comfortable, quiet and relatively grippy for an AS tyre. I'm looking forward to trying the ComforTred when my Integritys wear out.

[tomdeimos]

Clearly this thread alone is proof enough we need legislation to force people to buy greener tires.

Why is everyone upset about this? We had to have legislation for seat belts, air bags, etc alll for the same reason. Nobody would buy them, and seems here most of the people here are looking for anything but greener tires for their Prius.

And I'm sure the goal is not to ban tires but to force manufacturers to spend the extra few pennies it costs to make tires all more efficient.

I expect all non-energy star appliances will be banned soon too. Just like the old 6 gallon flush toilets were.

[theorist]

<div class='quotetop'>QUOTE(tomdeimos @ Jun 29 2006, 09:17 PM) [snapback]278898[/snapback]</div>

Clearly this thread alone is proof enough we need legislation to force people to buy greener tires.
[/b]

I've got to get out of Lexington.

As it is, if a set of tires lasts 50,000 miles, one gets 30 mpg while the other gets 32mpg, the more fuel efficient tires save over 100 gallons of gas. If gas costs $3/gallon (with prices rising as fast as the rate of return), it's economical to spend $75 more _per_ tire for the more fuel efficient tires. If we change the situation to 52mpg vs 50mpg, it's nearly a 40mpg difference, economical at a $30 price premium per tire.

I probably place far too much faith in the rationality of my fellow man. Still, if we're going to force people, why not institute a one family - one vehicle law and ration gasoline with each person being limited to 10 gallons a week? :P