In 2003, he signed with Roush Racing and finished in the top-ten four times, but Odoban ended its sponsorship after 15 races, forcing the team to close down. He returned to driving his own car for the remainder of the season, but only finished one race at Lowe's Motor Speedway. Barrett continued driving for his team in 2004, and joined DCT Motorsports for the 2005 season, scoring his only top ten of the season at New Hampshire Motor Speedway. In 2006, Barrett ran a variety of Busch events for MacDonald Motorsports and McGill Motorsports, and ran some races for Stanton Barrett Motorsports in 2007. For the 2008 NAPA Auto Parts 200 at Circuit Gilles Villeneuve, Barrett fielded a ride for himself and his father Stan. In a race marred by rain, the two finished 25th and 39th, respectively.