The governing body for stock car racing said the action was taken chiefly because Busch used an inappropriate hand gesture and abusive language.
Busch was knocked out early in the race because of transmission problems. While in the garage area, he was videotaped using foul language while waiting to be interviewed on television.
The fine came three days after Steve Addington announced he would not return as crew chief for Busch's car next season.
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