I wasn't trying to give saltfli (or anyone else) a hard time, but why risk someone possibly giving you trouble if/when warranty repairs are required? Many dealers (insurance companies, etc) are real jerks and are always trying to weasel their way out of doing warranty (i.e. free) work. Not always, but a lot of shady people try to find some way to avoid doing free work.
There must be *some* place in your area which you can trust to change the oil properly and use quality parts (changing the oil & filter aren't that complicated, even for a teenager). I'm sure you can get someone to use the oil and filter you want.
Plus, you get some documentation that proves you had it done "professionally" and at the correct interval. How does a Pepboy's receipt prove you changed the oil on *this* car, or that you did it correctly, or that it was done at 5000 miles (or whatever). The date on the receipt doesn't show the car's mileage.
It just seems like an awfully big risk to take to save $20. As for the oil & filter selection, they are supposed to use Ford approved materials (and document it), otherwise they are liable. Either way, YOU have proof that you did what you were supposed to (and when you were supposed to).
I'm not trying to bust your balls (or ovaries, for the lady members). I'm only trying to protect you guys from possible grief down the road.