The commission used ISO 28580 rolling resistance test protocol and the rolling resistance coefficient as the metric for expressing rolling resistance.
The CEC then came up with an effective rating system that would allow consumers to gauge accurately and choose tires based on their RRC numbers, he said.
RRCs for more than 1,000 tires in more than 150 sizes and more than 125 brands are in the public domain, thanks to the commission rule-making, Tuvell said.
However, the pending rolling resistance labels from the National Highway Traffic Safety Administration are expected to use tire manufacturers' recommendation of a star rating system, which would be much less meaningful to consumers and retailers than RRC numbers, he said.
Under the proposed system from the Rubber Manufacturers Association, he said, two tires far apart in RRC numbers could be given the same number of stars, or a tire very close in RRC to another could be ranked one star lower.
“Under the star system, manufacturers only report grades, with no actual RRC data,” Tuvell said.
He maintained that those grades “are not reliable. They are confusing, and they have no practical meaning to consumers or retailers.
“Any tire manufacturer could voluntarily provide RRC data.”
“Why do tire manufacturers refuse to provide RRC data?” he asked “Is it fear of competition?”
An effective tire fuel efficiency rating system, Tuvell said, would feature a complete RRC database on a searchable, interactive website, complete with an Internet learning center and a fuel savings calculator.
With all pending or extant tire quality grades, the biggest problems have been to instruct the public as to how to use them, according to George Gillespie, a former NHTSA official who is president and CEO of Gillespie Automotive Safety Services.
“All agency actions and rating systems need indoctrination,” he said in his ITEC presentation.
“All regulatory actions and TPs (test procedures) are subject to interpretation, and no rating system is intuitive,” the executive said.
NHTSA's Office of Vehicle Safety Compliance has an active outreach program to keep manufacturers informed about new safety standards, TPs and enforcement policies, according to Gillespie.
He said he hoped NHTSA will make sure the pending consumer education program for the tire fuel efficiency program will reach the widest possible audience.
“UTQGS (the Uniform Tire Quality Grading System) has a bad rap in part because there was no training,” he said.
In his opinion, tire identification number reading, basic tire pressure information and basic information about tire aging should all be part of the curricula in state-level driver's license training, he said.