Ron Stone, 34, played in all 16 games for the Raiders but has been plagued by inconsistency.
Ted Washington, who turns 38 next month, was the team's starting nose tackle. He is a veteran of 14 seasons and currently coaching in NFL Europe. He started all 16 games in '05 and recorded 47 tackles and one forced fumble.
Denard Walker, 32, was inactive for much of the 2005 season and held a $4.5 million cap figure.
Oakland is still approximately $12 million over the $94.5 million cap.
The team is discussing restructured deals with several players and could part ways with Kerry Collins in the next couple of days.