In between the 2003 and 2004 seasons, Sauter signed with RCR to run the full Cup schedule and also with Brewco Motorsports to run the full Busch Series schedule. He joined teammates Kevin Harvick and Robby Gordon and crew chief Kevin Hamlin at RCR. Sauter ran the full Busch schedule, performing well on short tracks. However, he was released after thirteen Cup races. 