NHTSA steps up investigation of tire valves … but not enough
Late last month the National Highway Traffic Safety Administration (NHTSA) upgraded its ongoing investigation into suspected defective tire valves imported by Dill Air Controls Products to what it calls an Engineering Analysis. Should the agency’s analysis find that Dill tire valves are indeed defective, the result could be a massive recall of approximately 23.5 million tire valves installed from August 2006 through July 2007.
NHTSA originally opened an investigation as a Preliminary Evaluation on May 15 following the fatal rollover crash of a 1998 Ford Explorer that allegedly was the result of a faulty Dill tire valve. On September 8, according to NHTSA, another serious crash involving a 2001 Toyota Sienna appeared "to be related to a cracked and leaking Dill tire valve.” To date, there have been more than 4,700 complaints filed with NHTSA’s Office of Defects Investigations regarding faulty Dill valves. And a vehicle inspection program conducted by the major tire retailer Discount Tire from April through June 2008, uncovered approximately 23,000 defective Dill valves.
According to reports filed with NHTSA, Dill imported valve stems from a manufacturer in China, Shanghai Baolong/ Topseal Automotive that lacked adequate ozone protection, which can cause the rubber to crack prematurely. Affected valves exhibit visible cracks shortly after being installed. Over eight to 14 months of use, the cracks can grow large enough to cause air leakage. Driving on under-inflated tires can cause tire damage and, eventually, cause the tires to fail or blow out.
Tech International, an importer of tire valves made by the same Chinese company that makes Dill tire valves, has already recalled some 6 million defective valve stems that it distributed. To date, Dill has not issued a recall of the tire valves, although it has posted advisories on its web site. Discount Tire stores that sold Dill valves from August 1, 2006 through July 31, 2007 sent letters to their customers warning them of the problem. We hope that other retailers who have sold the valves act as responsibly.