Tomlinson gained 56 yards on 18 carries and scored touchdowns in the first and second quarters.
Phillip Rivers completed 16-of-25 passes for 249 yards, one touchdown and one interception.
Linebacker Shawne Merriman made two of five sacks for San Diego, giving him 8 1/2 in his last five games against the Raiders. Vincent Jackson caught eight passes for 103 yards with one touchdown for the Chargers (4-3), who have split their last four contests.
The Chargers out-gained the Raiders 346-180 in total yards.
Oakland's JaMarcus Russell had 109 passing yards with one interception.
Justin Fargas rushed for 59 yards on 18 carries with one touchdown. Zach Miller had five receptions for 52 yards and Sebastian Janikowski kicked three field goals for the Raiders (2-6), who have lost five of six.