Over the weekend, hundreds of people used the Internet to circulate thousands of videos that charged GM with contributing to global warming, protested the war in Iraq or just demeaned the Tahoe's quality. Some videos also contained profanity or sexually explicit messages.

Late Monday, GM announced that it would begin screening the ads for "offensive and inflammatory" content but would not remove material based solely on a "negative tone" toward the company.

In one contest entry were the words "Yesterday's technology today," superimposed over a clip of engine pistons pumping. Another featured shots of the Tahoe zooming through snow, mountains and desert. Over the video appeared the words: "Global warming isn't a pretty SUV ad. It's a frightening reality."

"The issue here is that GM is providing a public display of the feedback versus keeping it in house," said Gordy Abel, vice president of marketing agency Carat Fusion. "An open community can see all responses. In my opinion (GM) needs to do a better job of screening these types of contests in the future to make sure the content complies with the rules before it is posted."