My wife's car is a 2007 Fusion SE. Owner's manual says two different specs, 1 for US and 1 for Canada:
Motorcraft SAE 5W-20
Premium Synthetic
Blend Motor Oil (US)
Motorcraft SAE 5W-20
Super Premium Motor
Oil (Canada)
There is footnote after (Canada) which states:
Use of synthetic or synthetic blend motor oil is not mandatory. Engine oil need only meet the
requirements of Ford specification WSS-M2C930-A and the API Certification mark.
So why the difference in specs between countries?
My wife paid $34 for an oil/filter change 6 months or so ago at one location, and today it cost $90 at another location because they said the specs on the car called for the premium synthetic oil. We ain't paying $90 again so I need to get this cost lowered. I'm guessing I will get the biggest cost cutting by using convention oil.