SRS Again Presses NHTSA for Consumer-Friendly Tire Date of Manufacture

Reprinted from The Safety Record, V3, Issue 3, Nov. / Dec. 2006

REHOBOTH, MA – Safety Research & Strategies has renewed its call for the National Highway Traffic Safety Administration to require tire makers to mold an easy-to-read date of manufacture on a tire’s sidewall.

SRS submitted comments on December 20 urging the agency to separate this proposal from the more complicated tire performance rulemaking. SRS President Sean Kane argued that now is the perfect time for NHTSA to consider implementing a new date of manufacture labeling regulation, while tire manufacturers gear up to meet their obligations in 2009 to mold the entire Tire Identification Number (TIN) on the intended outward sidewall of each tire. In November 2004, SRS petitioned the agency for a rulemaking to require that tire makers mold a non-coded date of manufacture on their products as a step toward reducing the number of aged tire failures. SRS argued that since the agency and the tire and vehicle manufacturers agree that tire age matters, consumers need an easy-to-read the date of manufacturer on the side of their tires. The agency denied the petition and instead chose to address the issue in its tire performance standards.

Since the 2004 SRS petition, three major tire makers have issued Technical Bulletins warning against the use of tires older than 10 years.

SRS bolstered its recent submission with a list of 108 incidents in which tires older than six years experienced a tread / belt separation, causing loss-of-control crashes that killed 82 and severely injured 115. The incidents were identified from litigation-the only public source of this data. The list only represents a fraction of the total, Kane argued, because less serious accidents go undocumented, uninvestigated or pursued through the courts.

“Because litigation serves as a bell-weather for trends,” Kane wrote in his submission, “We suspect that aged tires are contributing to a significantly larger number of failures than those we have documented.”

Those cases also illustrate the myriad ways aged tires end up in service. Nearly one-third of the cases involved unused or little-used spares, sometimes rotated into service by tire service technicians or automobile dealership personnel who were either unaware of the dangers of aged tires or were unable to read the date – currently an 11-digit alphanumeric code molded onto one side of the tire. In other cases, tires a decade or older were simply sold as new tires.

For example, on July 30, 2005, the right rear tire on Javier Rene Garcia Sr.’s Honda Accord failed as he drove on Texas Highway 359 south of Realitos. The Accord veered out of control into the path of a 2001 Chevrolet S-10 pickup truck. The failed tire was a Firestone-made Exxon branded Signature II made in 42nd week of 1991 even though it was purchased several months before. Garcia, his girlfriend and his seven-year-old son suffered fatal injuries. John Lee Woodall, the driver of the pick-up, sustained serious injuries.

Kane also reminded the agency of the 38-year history of the Tire Identification Number, during much of which the Rubber Manufacturers Association fought hard to keep the TIN molded on one side and the date of manufacture an obscure code.

In 1970, the National Highway Safety Board-NHTSA’s predecessor-declined to adopt the RMA’s internal system and proposed its own alphanumeric code. The NHSB proposed a system with four groups of symbols, to be read from left to right. The third group, consisting of four symbols, would identify the date of manufacture by
week and year. For example, 3171 would mean that the tire was made on the 31st week of 1971. In response, some tire makers complained that they didn’t want the customer to be able to interpret the code, think they were capable of reading it, or believe that it was necessary for the consumer to have that information.

BF Goodrich, for example, said that the consumer would be able to identify a recalled tire based on a defect notification letter that would use the entire serial number. Goodyear said that it was questionable that the consumer would be any better able to decipher the bureau’s proposed four-digit date code than the RMA’s two-digit code. Firestone in particular argued that the bureau should adopt the RMA’s two-symbol date code expressly because consumers couldn’t read it. “Tires are not perishable items,” Firestone said in its petition. “Therefore, a conspicuous disclosure of tire age would unavoidably introduce into the marketplace a totally artificial measure of quality unrelated to product performance and effectiveness.”

When the agency published the final rule in November 1970, the NHSB dropped the decade position, so that 311 would mean that the tire was made on the 31st week of 1971. The agency said that it shortened the date code and moved it to the last grouping to the last position to make it easier for manufacturers to shorten and change the stencil plate. The manufacturing date code remained a three-symbol group until 1999, when the agency publish a final rule based on petitions from the RMA and the European Technical Rim and Tyre Organization (ETRTO) requesting that the grouping signifying date of manufacture be expanded from three digits to four digits — as was first proposed in 1970.

In the post Ford Explorer-Firestone tire rollover period, the agency began to re-examine the efficacy of the TIN. To better understand the knowledge and desires of consumers, NHTSA contracted a series of eight focus groups to determine what consumers knew about tires and safety and what they would like to know. The agency’s research found that consumers were confused by the codes, but wanted to learn more about what they meant. Some wished that tire information were presented in “plain language.” Since they tended to believe that information provided on tires “is there for a reason,” they wished it was displayed in a more understandable format. Codes may be appropriate for the trade, they suggested, but not for consumers.

Despite this, the agency did not move toward a “plain language” standard. Instead, the agency’s major proposals included re-ordering the TIN information and requiring that the information be molded on both sides. The final rule, published in June 2004, gave manufacturers until September 2009 to ensure that consumers could read the TIN on the outboard side of the tire. This was a concession to tire manufacturers who argued it would cost $224 million to re-work all of the molds. Pushing the date ahead five years gave manufacturers time for current molds to wear-out, before their replacement.

“As the rule stands today,” Kane said in his submission, “consumers still have to wait three years before they get easier access to the TIN. However, consumers are no closer to understanding what these numbers and letters mean. Meanwhile, when manufacturers are reworking their molds to comply with other aspects of FMVSS 139, they could also be incorporating a change in the date of manufacture to a format anyone can understand.”

Copyright © Safety Research & Strategies, Inc., 2006

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