Busch will drive the No. 51 car, a Phoenix Construction Chevrolet Impala machine owned by James Finch.
"Now with Kurt Busch as our driver, we have a shot to win every week," Finch said. "He's a past champion and he's proven he can win everywhere. Our sponsors are looking forward to Kurt representing their brands."
Penske Racing released the volatile Busch one week after he was fined $50,000 for a confrontation with an ESPN pit reporter during the season-ending race at Homestead, Fla.
Busch has one Sprint Cup championship to his credit and he drove for Penske from 2006-11. He won 10 races with that team, including two in 2011.
Busch wound up 11th in the points standings this year, one spot ahead of younger brother Kyle.
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