An excellent website: bobistheoilguy.com
Look for the forums.
What you're doing is probably overkill (full synthetic and 3k OCI)...
OCI stands for "oil change interval"...
as long as your oil doesn't get dirty. That full synthetic can last much
longer, but then the main concern is when it gets dirty.
If you don't want to go with a longer OCI (5k would easily be fine) then
consider using a quality dino oil. This would cost much less, and with
dino, if you change it at 3k you're absolutley fine.
Check out the site above. People there do UOAs (used oil analysis) and
verify, for the most part, that they're not just blowing smoke.
For example, most people there love the Havoline brand due to the
high molybdenum content and excellent UOAs. This might be counter-
intuitive, because Havoline is also one of the cheapest.
With a Ford, use the excellent Motorcraft filters! In fact, they're back at
Wal-Mart, cheap!
Regards, Cliff