But NHTSA also criticized Graco in a letter dated Tuesday, saying the recall improperly excludes infant car seats with the same buckles. Both the company and NHTSA have received complaints about stuck buckles on the infant seats, the agency said.
"Some of these consumers have had no choice but to resort to the extreme measure of cutting the harness straps to remove their child from the car seat," the NHTSA letter said.
The agency wants Graco to identify the total number of seats that potentially have the defect and explain why it is pushing for the smaller recall.
Graco, a division of Atlanta-based Newell Rubbermaid, told The Associated Press that its tests found that food or beverages can make the harness buckles in the children's seats sticky and harder to use over time. The company will send replacement buckles for free to owners who registered their seats.
Owners who didn't register their seats but want free replacement buckles can call the company's consumer hotline at 800-345-4109 or visit its website.
Rear-facing infant seats aren't being recalled because infants don't get food or drinks on their seats, Graco spokeswoman Ashley Mowrey said. But Mowrey said Graco will send replacement buckles to owners of rear-facing infant seats upon request.
Mowrey said the company has issued cleaning tips for the buckles, and began sending replacement buckles to owners last summer. Graco is also sending instructions for how to replace the buckles and posting a video on its website to show parents how to replace them.
In documents sent to NHTSA, Graco estimated that less than 1 percent of the seats involved in the recall have had buckles that were stuck or difficult to unlatch.
Mowrey said there have been no reported injuries due to the defect.
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NHTSA, in documents filed last year, said it received 80 complaints about the seats.
In one complaint from October of 2011, a parent wrote that they tried to get a 20-month-old boy out of a My Ride seat, but the center release button on the buckle couldn't be depressed.
The parent was able to loosen the straps from the rear of the seat enough to free the child. "My biggest concern is that if this happens during an emergency, where we need to get him out quickly, we won't be able to without cutting the belt material," the parent wrote.
Two months before that, a family with a Graco MyRide 65 car seat told NHTSA that Graco wouldn't replace a sticking buckle on their car seat, but offered them $40 toward a replacement seat.
NHTSA does not identify people who file complaints to the agency, but it posts complaints on its website.
—By The Associated Press