Oakland scored 28 runs in the first three games of the series with the Tigers, allowing the A's to stay within 2 1/2 games of division-leading Texas in the American League West. The Rangers completed a sweep of Seattle Wednesday.
The 14 runs equaled a season-high for the A's, who defeated Toronto 14-6 on Aug. 9.
Oakland already had a 3-1 lead when an RBI double by Moss kicked off a four-run fifth. He then hit a two-run blast in the sixth and added a three-run shot in the eighth.
Dan Straily (7-7) was the benefactor of the onslaught, getting the win by giving up a run on eight hits in six innings.
Doug Fister (11-7) was pummeled for seven runs on 13 hits in five innings.