Bob Osborne cited undisclosed health concerns in his decision to relinquish the No. 99 Ford, which has been stuck in a slump since Edwards ended last season tied with Tony Stewart in the Chase for the Sprint Cup championship. The title went to Stewart on a tie-breaker.
"At this time in my life, however, concerns with my health have necessitated that I change my role within the organization."
Osborne, who guided Edwards to 18 wins and two runner-up finishes in the points, will move to a senior management position with Roush Fenway Racing. He'll be replaced as crew chief by Chad Norris, who has been with Roush since 2005 as a crew chief in the Nationwide and Truck Series.
"This transition is not an easy one, but I'm thankful to have the full support of Jack (Roush), Carl and the entire organization. I also have every confidence in Chad Norris, and I look forward to working with him as we continue to pursue a championship in 2012," said Osborne, who asked for privacy from the NASCAR community.
Osborne had run the No. 99 team since 2004, and Edwards took over that ride for the final 13 races of that season.
But Edwards is stuck in a 52-race losing streak dating back to Las Vegas last season, and at 11th in the point standings he's in danger of missing the Chase this season. Edwards has only worked with Osborne at the Cup level.
"I cannot say enough good things about Bob Osborne," Edwards said. "I'm so thankful for what he's done for me as a driver, and he is without a doubt one of the smartest guys in the sport. I'm also appreciative of the fact that he'll continue to be a resource for me and our team as we focus on these final races."
Norris since last season has led Roush Fenway's testing program, and has been crew chief for Ricky Stenhouse Jr.'s limited Sprint Cup Series schedule and Trevor Bayne's partial Nationwide Series schedule.
Norris led Bayne to his inaugural Nationwide Series win at Texas Motor Speedway in November of 2011.
"We're very fortunate to have Chad Norris as part of our organization to take over for the No. 99," Edwards said. "I've known Chad for a long time and he is a fierce competitor. We've got our work cut out for us over the next seven races, and I've got every confidence Chad can lead our team to where we need to be."