The tire industry is no happier with the new final rule on tire pressure monitoring systems than it was with the old one, according to the Rubber Manufacturers Association (RMA).
The new standard issued April 7 still maintains the requirement that a tire pressure warning light should illuminate only after one or more tires on a vehicle falls 25 percent or more below the vehicle manufacturer's recommended air pressure. This, the RMA claims, is simply inadequate to protect motorists from the tire damage and accidents caused by severely underinflated tires.
``We support tire-pressure monitors that provide a timely low-pressure warning to motorists,'' said RMA President Donald B. Shea in a news release. ``Unfortunately, this regulation may give motorists a false sense of security that their tires are properly inflated when they may be significantly underinflated.''
Supported by organizations including the Tire Industry Association (TIA) and the American Automobile Association (AAA), the RMA petitioned the National Highway Traffic Safety Administration (NHTSA) for a tire pressure reserve requirement to ensure that a vehicle's tires could still carry the vehicle's maximum load at the point the tire-pressure warning light comes on.
Responding to the RMA, the agency noted its 1981 report that showed no correlation between tire failure and reserve load, but it promised to conduct a new, more comprehensive study of the question. The new final rule discussed the question of tire reserve load, but postponed a decision on the RMA petition for a separate notice.
As issued, the new standard will be phased in starting Sept. 1. By the 2008 model year, all new vehicles weighing 10,000 pounds or less must be equipped with tire-pressure monitoring systems.
According to the rule, the yellow warning light must illuminate within 20 minutes of first recording a low pressure, traveling at speeds of 50 to 100 kilometers an hour.
While the agency does not mandate that monitoring devices be compatible with replacement tires, it does require a malfunction indicator to warn motorists if and when replacement tires are incompatible with their tire monitoring systems. The lack of any provision for replacement tires in the proposed revised rule issued last September was a sore point with tire makers, tire dealers and consumer groups alike.
The rule also requires vehicle owner's manuals to contain language explaining the purpose of tire-pressure monitoring systems, the meaning of the warning light and the consequences of driving with severely underinflated tires.
Of all the rulemakings mandated by the Transportation Recall Enhancement, Accountability and Documentation (TREAD) Act of 2000, none has created more trouble for NHTSA than the one on tire-pressure monitoring systems.
Writing the original version of the standard in 2002, the agency first wanted to mandate devices that monitored a vehicle's tire pressures directly. However, the Office of Management and Budget (OMB) refused to sign off on the rule unless NHTSA rewrote it to allow the use of indirect monitoring systems that monitored tire pressures through the operation of a car's anti-lock brake system.
When that rule appeared in June 2002, the consumer watchdog groups Public Citizen, the Center for Auto Safety and the New York Public Interest Research Group sued NHTSA before the Second Circuit federal appeals court in New York.
It was unconscionable, they argued, that the agency wouldn't mandate the vastly more effective direct monitoring systems, especially when they would cost less than $10 more per vehicle. They also blasted the auto makers, accusing them of pressuring OMB on indirect monitoring systems as a back-door way of selling ABS systems to motorists.
The Second Circuit agreed and overturned the rule in August 2003, sending it back to NHTSA for revision.
Joan Claybrook, president of Public Citizen and a former NHTSA administrator, said she was pleased for the most part with the new standard, despite quibbles with the 25-percent and 20-minute provisions. Her group had favored a 20-percent warning threshold after 10 minutes of running with low pressure.
``Finally we have an appropriate tire monitoring rule,'' Ms. Claybrook said. ``That's a big victory, given the administration and the industry's recalcitrance.''
TIA officials were traveling at press time and were unavailable for comment.