HOLD ON, HOLD ON. May I debunk a few myths here. I did my thesis in Oil Filtration when in engineering school, which don't make me right, just keen on the subject:
SYNTHETIC OIL DOES NOT, REPEAT NOT, PERMIT A EXTENSION IN OIL REPLACEMENT FREQUENCY.
You MUST stick to Fords frequency, depending on whether you are using your vehicle in severe use (which most of us are in stop start driving) or regular.
You MUST stick to 5-20. The reason is that 90% of all engine wear occurs during start up and Ford has determined that this is a requirement. You will invalidate warranty if you do otherwise. Our local dealers here in Canada are very helpful and supply the oil at the same or lower price to their competitors
Synthetic oils give superior lubrication (and by extension extended engine life) at temperature extremes, whether its worth the extra money when most people replace their vehicles at 200,000km give or take, is a moot point
Transission. Flush and replace every 50, 000km for severe. Be careful, many lube places say they flush and when you go looking for the pump, its nowhere to be found!
Hope this helps | 
