One-Third of Tires May Fail Stricter Standards
About a third of the 287 million passenger car and truck tires sold in the United States every year might fail new standards spurred by the Firestone tire crisis, according to U.S. auto safety regulators.
The National Highway Traffic Safety Administration says that although some tires would have to be redesigned, the new rules could save 27 lives and prevent 667 injuries a year from crashes caused by blowouts or other tire failures. It also estimates the standards would cost the tire industry $282 million annually.
Tire makers contend that the rules are unnecessarily severe and would cost the industry far more than NHTSA estimates. The agency had a June 1 deadline for a decision, but the debate has pushed the deadline back indefinitely--one of several delays the agency faces in putting new safety rules in place.
“We agree with NHTSA that tire tests need to be updated,” said Dan Zielinski, spokesman for the Rubber Manufacturers Assn. “We just think they need to be more reflective of real-world conditions.”
The 271 deaths and more than 800 injuries linked to tread separation and other failures of tires made by Bridgestone Corp.’s Firestone unit, mostly on Ford Motor Co. Explorer sport utility vehicles, spurred Congress to order a rewrite of federal tire standards that have not changed since 1967.
The Firestone tires were found to have manufacturing defects that left them susceptible to losing their tread, especially at high temperatures.
Although data on tire-related crashes are sketchy, NHTSA estimates that about 414 deaths and 10,275 injuries a year might be caused by tire failures. NHTSA’s research also found that heat is a common factor in all tire failures, with the highest rate of accidents in Southern states during summer.
Two of the new tests would be tougher versions of current measures, such as doubling the length of the endurance test to 3,278 miles.
Congress also required NHTSA to order all new vehicles to come with a tire-pressure monitor. But because many owners will not check their tire pressure until the monitor goes off, the agency wants tires to perform for a short time at low inflation levels to ensure an extra margin of safety.
One proposed test would take the tires from the endurance test and run them under-inflated for 90 minutes at speeds up to 99 mph.
All the new standards combined would flunk 33% of current tires, according to limited tests conducted by NHTSA. It also warned that its tests found wide differences in the performance of tires that should have been identical.
The Rubber Manufacturers Assn. also has proposed less stringent tests that NHTSA says all modern tires probably would pass.
