had my oil changed today (2006 Crossfire) the mechanic showed me some oil on the pan that covers the bottom of the engine. The oil seemed to be leaking from the drivers side of the engine. Very difficult to see from above or below engine. The leak appears to be minor--is this a gasket? Should I take it to a Chrysler or Mercedes Dealer. The car has 25000 miles and its been several years since the oil was changed--the old oil didn't seem dirty but I was concerned about the time between changes