Federal requirements for grading a tire's treadwear, traction and temperature resistance are meant to help the consumer compare the numerous tire choices in the marketplace, yet the Uniform Tire Quality Grading (UTQG) system often is criticized for consumer confusion and manufacturer manipulation.
The UTQG is a tire information system designed by the government to help buyers make relative comparisons among tires, according to the National Highway Traffic Safety Administration (NHTSA). The federal agency said it plans to review the system.
The agency readily admits UTQG is neither a safety rating nor a guarantee that a tire will last for a specified number of miles or perform in a certain way. The grading, it said, simply offers consumers additional information to combine with other considerations, such as price, brand loyalty and dealer recommendations.
``UTQG ratings are a combination of technical and marketing driven numbers,'' said Raymond Labuda, vice president of tire technology for Hankook Tire Co. Ltd.'s technical center in Akron. He noted that in deciding on a tire's treadwear grade, the manufacturer typically will take into consideration the ratings of competitors' tires and where it will be positioned within the company's own product lineup.
But that combination is part of the problem, critics say.
According to the Consumers Union's comments to NHTSA on tire identification and recordkeeping regulations in January 2001, the consumer group ``continues to view UTQG treadwear designation with skepticism.
``A tire's assigned grade is more a marketing device than a true measure of treadwear. It requires calculation which provides only a comparison among tires, with no realistic measure of expected mileage,'' the group said.
R. David Pittle, the organization's senior vice president of technical policy, said in an address to the Clemson University Tire Industry Conference in February that despite government efforts to provide meaningful treadwear comparison among tires, ``the grades are unintuitive and provide more confusion than help.
``Self-certification (by the manufacturer) makes it impossible to compare models from different manufacturers. Codes are not directly translatable to actual mileage,'' he said. ``Because of the testing procedures, the UTQG is probably less of a good thing.''
Roy Littlefield, executive vice president of the Tire Industry Association (TIA), said because of the testing procedures, UTQG probably is less useful in comparing the products of different manufacturers than when choosing between those of a single tire maker.
``I am not convinced that it is widely used by consumers,'' Mr. Littlefield said. ``For consumers who do use it, I believe that more would be concerned with treadwear than with safety issues.''
According to a 1992 NHTSA evaluation of UTQG standards and other tire labeling requirements, of some 140 ``potential consumers'' surveyed (those who planned to purchase tires within two months), more than half that group rated information about all three UTQG criteria important in making tire purchase decisions.
But out of another 369 ``recent consumers'' surveyed (those who bought tires within the past six months), less than 50 percent rated UTQG information important in influencing their tire purchase decision.
Most survey respondents in this latter group knew the correct definition of the temperature resistance rating and the relative ranking of two traction grades, but less than half the consumers knew the correct definition of traction rating.
The NHTSA evaluation also reported that before buying tires, 72 percent of the recent consumers said they examined the current tires on their vehicles for information to help in purchase decisions.
``With the Internet today there is more information on tires out there than ever before. So it comes down to a question of how much research a consumer really wants to put into buying a tire,'' said Hankook's Mr. Labuda. ``To a lot of people, buying tires is like going to the dentist. They want the dealer to put a set of tires on their car, and they may not want to know a lot about it.''
NHTSA said it plans to review the UTQG program and possibly make adjustments. But it gave no timetable of when this review would happen. The agency said it believes there still is a need for UTQG.
``We get calls from consumers asking about the ratings, and they confirm that UTQG does provide relevant information to help them compare tires in three areas of safety concerns, i.e., traction, treadwear and resistance to temperature,'' a NHTSA spokesperson said.
According to the agency, most of the consumer calls it receives involve requests for explanation of the ratings or ``complaints if the tire does not perform up to expectations, possibly due to tire care and maintenance and local road and environmental conditions.''
To verify a tire's grading, NHTSA purchases tires from the marketplace and conducts traction tests on a government test track. The UTQG program has a $367,000 annual budget, according to NHTSA, which employs three at its San Angelo, Texas, testing facility and receives assistance from the Office of Vehicle Safety Compliance staff at its headquarters.
The agency does not recreate the actual treadwear test but carries out testing that, it said, supports the treadwear tests done by tire manufacturers.
In a typical fiscal year, the agency said it tests 50 tire brands for traction performance. And in 2002, all the test tires' results agreed with ratings assigned by the tire manufacturers, NHTSA said.
(The NHTSA Web site, http://www.nhtsa.dot.gov/cars/testing/utqg/table_1.htm#Brand, publishes the results of its traction testing and the UTQG treadwear ratings provided by tire manufacturers.)
But no matter what the grading, NHTSA and tire manufacturers agree that proper tire maintenance is the final denominator. ``The highest rated tire in the world will not do the job if it is overloaded, underinflated and/or bald,'' noted Mike Wischhusen, director of industry standards and government regulations for Michelin Americas Small Tires.
Is there a better way to rate tires? ``The UTQG is a yardstick, not a perfect one, but the best one we have at the moment,'' Mr. Wischhusen said. ``These are federal government standards, but the manufacturers perform the test themselves, so there is some question as to whether comparing UTQG ratings between and among brands is an accurate way of evaluating these performance characteristics.
``Still, I think it's safe to say that a UTQG of 200 in treadwear will provide more miles than one with 100. Whether it will provide twice as many miles is really just a ballpark estimate.''
But some critics say those estimates are skewed.
``A lot of manufacturers use the lowest common denominator in setting UTQG grades to protect themselves against litigation, which they shouldn't do. I want to see NHTSA publicize UTQG, which it doesn't do,'' said Joan Claybrook, president of Public Citizen and a former NHTSA administrator.
Consumer Reports magazine's automotive and tire test engineers believe there can be a better way of making the information on the tire sidewall more intuitive for consumers.
``We're looking for stuff that's easy to equate to the consumer,'' said Eugene Peterson, senior automotive and tire test engineer. ``Treadwear: Just give me a good treadwear allowance (for example) `This tire is good for ``X'' amount of miles.' Don't tell me its two and a half times better than a reference tire rated at a 100. That's what people want to know.''
The traction grades are probably the most meaningful of the UTQG grades for the consumer, according to Consumers Union, the non-profit publisher of Consumer Reports, and could even be expanded to include greater differentiation, through additional grades and expanded testing for snow, ice or mud traction capability.
Currently, the gradings are comparative grade designations for treadwear, traction and temperature for all passenger car tires, except deep-tread snow tires, space-saver or temporary spares, or tires with normal rim diameters of 12 inches or less.
* The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. The grade is a percentage of the NHTSA nominal treadwear value. For example, a tire graded 150 would wear 11/2 times as well on the government course as a tire graded 100. But NHTSA notes that the relative performance of a tire depends upon the actual conditions of its use. So its actual wear rate can be affected by variations in driving habits, service practices and differences in road characteristics and climate.
* The traction grades, AA (the highest), A, B and C, represent the tire's ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete. The grade does not reflect cornering traction. A tire marked C may have poor traction performance.
* The temperature grades, A (the highest), B and C, represent the tire's resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel. Sustained high temperature can cause the material of the tire to degenerate and reduce tire life, and excessive temperature can lead to sudden tire failure. The grade C corresponds to a level of performance which all passenger tires must meet under the Federal Motor Vehicle Safety Standard No. 109. Grades A and B represent higher levels of performance on the laboratory test wheel than the minimum required by law.
A tire is considered to have successfully completed a test stage if, at the end of the test stage, it exhibits no visual evidence of tread, sidewall, ply, cord, innerliner or bead separation, chunking, broken cords, cracking or open splices. A tire is graded C if it fails to complete the 500 rpm test stage specified; graded B only if it successfully completes the 500 rpm test; and graded A if it successfully completes the 575 rpm test stage.
Free-lance writer Chuck Slaybaugh and Tire Business Staff Reporter Miles Moore contributed to this report.