Search on this subject turned up a bazillion conflicting opinions but no specifics on Ford capacity / type recommendation. Glove box handle is broken off so have not been able to get to owners manual. I want to change the oil this weekend but don't know oil capacity or (Ford's) oil type recommendation. I'd like to go synthetic due to the high revving nature of the engine. Can AMSOIL be purchased locally, or does it have to be ordered from the factory?