"The way we see that is it's a pretty strong vote of confidence in our products," Tom Henderson said.

GM launched the money-back guarantee program on Sept. 14 with an advertising blitz, including TV spots with GM Chairman Ed Whitacre, in a bid to get on-the-fence vehicle buyers to consider GM products despite the company's stint in bankruptcy court this summer.

Customers can also waive the return policy in exchange for a $500 rebate toward the purchase of their vehicle. Henderson said only about 400 vehicle buyers — or "less than 1%" of all vehicles sold since the program launched — have chosen the return policy over the $500 rebate.

The program runs through Nov. 30 and allows customers to return any new 2009 and 2010 Chevrolet, Cadillac, GMC or Buick vehicle for a refund of the purchase price and sales tax if they are unsatisfied with their vehicle.

The policy allows buyers to return their vehicle between day 31 and day 60 of ownership, meaning the first refund requests started coming in on Thursday. Reasons for the returns have been "across the board," he said.

One returnee was the buyer of a Chevrolet Corvette, who bought the sports car with a manual transmission and found it "painful to shift," GM Vice Chairman Bob Lutz told reporters during a briefing last week. Once the buyer returned the Corvette, he wound up exchanging it for the same model — but with an automatic gear box, instead.

The return had nothing to do with dissatisfaction with the car other than the choice of transmissions, Lutz said.

"He brought it back because he made a mistake," he said.

A report Monday by CNW Research said the program has been successful in getting consumers to consider buying GM products. The program has "spiked interest in the company's products far beyond any recent previous effort," the research firm said.

AP Auto Writer Tom Krisher contributed to this report from Detroit.