More than half a million GMC Sierra pickup trucks are under federal investigation after drivers complained that pieces of their grilles were flying off on the road. Some owners even said the problem continued after their trucks had already been repaired under a previous recall.

The National Highway Traffic Safety Administration (NHTSA) opened an investigation on October 9, covering approximately 535,639 GMC Sierra 1500 trucks from the 2022 through 2024 model years.

According to GM Authority, 118 complaints were received concerning upper grille deflectors detaching while vehicles were on the road.

In some cases, the flying parts cracked windshields and forced nearby drivers to swerve to avoid being struck by debris.

However, what makes the investigation particularly concerning is that 21 complaints involved trucks that had already received repairs under a previous recall.

General Motors recalled 70,768 GMC Sierra 1500 trucks in February 2025 over concerns that the pieces holding the chrome grille trim in place could break, which could cause it to come loose.

Dealers were instructed to reinforce or repair the attachment points at no cost to owners.

The original recall covered certain 2022 models equipped with chrome grille deflectors, but it left out other 2022 trucks, along with all 2023 and 2024 models.

Federal investigators are now examining whether the recall included enough vehicles and whether the original repair actually addressed the problem.

According to GM's original recall documents, drivers may notice a rattling noise before the grille deflector completely detaches from the vehicle.

No crashes, injuries or deaths were identified in the new investigation's opening documents.

While the investigation doesn't constitute a new recall, regulators still haven't determined whether additional repairs will be necessary.

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