I am just using your standard Motorcraft 5W20 (yep, you read it right). Ford has now gone to a 20-weight oil for most of its cars. The way I drive, it makes it really expensive to go synthetic every oil change (I change my oil once a month).
Ford's new service routine suggests that if you do city driving, change it the usual 3 months/5,000 km. For highway, go for 6 months/10,000 km. Last bit scares me though...waiting that long for oil...erm...no.
