The No. 21 debuted in 2000, with Rockwell Automation as the sponsor and Childress' son-in-law Mike Dillon as the driver. Dillon posted two Top 10 finishes and finished 23rd in points that year. Six races into 2001, he was injured at Bristol Motor Speedway and it was announced at the time he would be out for the rest of the season. Since then, he has taken on other roles with the team. His replacement was Mike Skinner but after his injury, Jeff Purvis briefly took over, winning at Pikes Peak, before Skinner returned. After Skinner's release, Robby Gordon had the driving duties for the balance of the season.