NHTSA Seeks Federal Tire Rating System That Includes Fuel Economy Index
By Scott Doggett June 23, 2009
Borrowing an idea from California's air-quality regulators
, federal authorities today proposed creation of a label (pictured
) that would, for the first time, include information about a tire's impact on fuel economy and global warming.
Under the U.S. Transportation Department proposal, tire manufacturers would be required to affix such labels to replacement tires sold in the United States.
The label is, we think, a good idea. The 240 million passenger cars and light trucks in the U.S. consume about 135 billion gallons of motor fuel annually.
Finding ways to reduce this energy consumption should be a national goal for reasons ranging from ensuring economic and national security to improving local air quality and reducing greenhouse-gas emissions.
As you can see from the proposed label, consumers would also receive information about the tire's performance characteristics as well as their "greeness."
The proposal requires tire manufacturers to label their replacement tires for fuel efficiency (via rolling-resistance tests), safety (via traction tests), and durability (via treadwear-life tests) based on test procedures specified by the National Highway Traffic Safety Administration.
A measurement of traction is intended to indicate a tire's ability to stop on wet pavement. Thus, traction is one metric that corresponds to safety. A treadwear rating measures a tire's wear rate compared with that of control tires. Treadwear life, therefore, corresponds to a measure of durability.
Comparing this new proposed label across potential replacement tires would enable consumers to see how different replacement tires can affect the fuel economy they are getting from their vehicle.
The label would also allow consumers to see the tradeoff they may be facing between fuel efficiency, safety (i.e., traction), and durability (i.e., treadwear life), and how the balance of these factors may differ from tire to tire.
The NHTSA's research has found that while tire construction need not sacrifice traction or treadwear for improved fuel efficiency, maintaining the same traction and treadwear while increasing the fuel efficiency of a given tire often entails higher costs.
So, if a manufacturer seeks to improve the fuel efficiency of a given replacement tire construction while keeping cost constant, there's a good chance that the construction will sacrifice either traction or treadwear.
The Rubber Manufactuers Association, representing eight tire manufacturers, says the new testing needed to rate the tires will incur more than $20 million in industry costs and opposes the labels.
LEAVE A COMMENT