General Motors Corp. yesterday tried to persuade the National Highway Traffic Safety Administration not to recall about 280,000 Chevrolet Tahoe and GMC Yukon sport-utility vehicles because of what the agency thinks are unsafe air bags in the front passenger seat of the trucks.

"There is nothing wrong with the air bags in GM's 1999 full-size sport-utility vehicles. In the event of a crash, these vehicles provide occupants with the safety and protection that they expect and deserve," said Robert Lange, GM's engineering director.

In a government test last February on a male dummy in a 1999 Tahoe, the vehicle exceeded the limits set by the agency for neck injuries when a crash occurs and the air bag deploys.

But, in a filing with the agency, GM maintained that the test results were "a technicality"--outside the scope of the time measurements NHTSA uses to determine when a neck injury from an air bag occurs. According to GM, a real-world crash lasts 130 milliseconds, and NHTSA found the problem at 170 milliseconds.

"Neck extension measures on the dummy taken during this time period are not covered by the regulation," GM said. "Even if they were covered by the regulation, the measure was so low that it would not create a significant increase in risk to the safety of an unbelted occupant."

GM first asked NHTSA on June 10 to disregard the test because it was "inconsequential to motor vehicle safety." Five consumer groups opposed GM's petition, saying the air bags deflate too quickly and don't protect against serious neck injury.

NHTSA spokesman Tim Hurd said the agency is reviewing the new research GM submitted and has not made a decision on whether to recall the vehicles.