Carson Palmer threw for 237 yards and one touchdown but was intercepted twice on 16-of-26 passes for the Raiders (8-7), who moved into a tie atop the AFC West standings with Denver, after the Broncos were routed in Buffalo.
Denarius Moore finished with 94 yards and a score on four receptions, while Michael Bush added 70 yards on 23 carries.
Oakland hosts San Diego -- which plays in Detroit later Saturday -- in its season finale next Sunday.
Kyle Orton completed 21-of-36 passes for 300 yards, one TD and two picks for the Chiefs (6-9), who couldn't sustain momentum from knocking off the previously-unbeaten Packers last week.
Dwayne Bowe registered the game-tying touchdown late in the fourth, part of an 80-yard, six-reception contest in the setback.