The latest woe for General Motors may sound a bit familiar. It appears the car manufacturer knew of a potential safety problem — in which a loose bolt could cause loss of the driver’s seat function — before affected vehicles ever hit the market, but didn’t take action until issuing a recall earlier this month.

According to a report from The Detroit News, General Motors received at least 27 warranty claims and reports of problems in a number of vehicles produced in 2011, but failed to take action until recalling 414,000 vehicles for faulty bolts last week.

The bolt that secures the power front seat height adjuster can become loose or fall out. If that occurs, the seat will suddenly drop to the lowest position and the sudden movement could impair the driver’s ability to safely operate the vehicle, increasing the risk of a crash.

In a notice [PDF] to the National Highway Traffic Safety Administration, GM says it first learned of the problem in April 2013 when the company’s engineering team identified a noise complaint on a Buick Regal pre-production durability test vehicle at the GM Milford Proving Grounds.

Officials with the company determined at the time that there was no loss of seat function and the issue was classified as a customer annoyance.

“The root cause of the noise issue was found to be a clamp condition on the height adjuster spindle bolt and seat cushion frame caused by poor extrusion on the height adjuster spindle bracket. The spindle bolt had become loose but did not fall out,” GM officials say in the notice.

But just two months later a customer filed a field complaint alleging that the power driver seat in his Camaro moved while driving, causing a rear-end collision with another vehicle.

In July 2013, GM inspected the vehicle and found that the bolt on the component of the seat height adjuster motor that raises and lowers the seat had fallen out.

GM then contacted the seat frame supplier to obtain design and manufacturing specifications regarding the Camaro claim. The documents provided found the build date of the vehicle involved in the field claim to be March 2011.

Warranty data provided on GM’s Camaro model indicated that, to date, 27 cases of loose or missing height adjuster bolts have been reported. However, GM says none of the other claims involved crashes or injuries, thus the manufacturer decided that “no effect on vehicle safety was determined.”

This May, in the wake of GM’s most recent issues, the manufacturer assigned an investigator to take another review of the initial performance information by Engineering Analysis.

Investigators determined that warranty data for height adjuster spindle bolt repairs had an elevated rate of claims for vehicles built beginning in July 2010 through July 2011. The issue was found to be in relation to a change in the supplier used by the company.

“It was discovered that a component supplier source change occurred in October 2010, and the tool move to the new supplier was completed in January 2011. Parts were banked prior to the move, and were depleted in
production in July of 2011. It was also learned that a tool refurbishment took place in January 2011.

During the Camaro claim investigation it was concluded that poor extrusion on the height adjuster spindle bracket was the cause of loss of the bolt in the Camaro and vehicles built during the same time frame. A review of warranty data also indicated that warranty rates for vehicles built after July 2011 were not elevated.”

These finding resulted in the July 23 recall of 414,333 vehicles including the Chevy Camaro (model year 2011-2012); Chevy Equinox (2010-2012); GMC Terrain (2010-2012); Buick Regal and LaCrosse (2011-2012 for both); Cadillac SRX (2010-2012).

Owners of the vehicles are urged to not use the power height adjustable feature until dealers can replace the height adjuster bolt.

This most recent issue appears to be another case of GM officials waiting to issue a recall even though a safety problem was documented in thousands of vehicles.

Earlier this year it was revealed that some GM officials knew about a possible ignition switch defect back in 2005, but failed to take action until early 2013 when it began to recall millions of vehicles. So far, that safety issue has resulted in at lease 13 deaths, but likely many more.

GM reviewed missing bolt cases in ’13 without issuing recall [The Detroit News]

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