there are numerous possibilities that could be your issue. is there high mileage? what type of oil is being used (i.e. 10w30 5w30) ?
if you spill oil, it will burn and that is probably what you smell when driving. it's just oil burning off. I have had 2 Fords ( one currently I have had for 10 years I might add). Ford has a tendency to be an oil burner. your vehicle could be in the same boat. As long as you are getting pressure in your block and the oil pump is working, I really wouldn't worry about. if the pan is leaking ( which you did not say that it was) easy gasket (liquid ) replace. I have found out that liquid gasket lasts longer than traditional fiber gasket.
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