Originally Posted By: 2010_FX4
There is more to this than just a myth and I think that Ford might know a thing or two about their engines since they designed them--a 50 grade oil is not for that engine and nothing heavier than a 20 grade is needed--wanted or desired is something else entirely.
There is nothing more to that myth, its just that and nothing more or less. Obviously they designed that engine to run on more than on one grade of oil. Proof? Ford GT500 5.4L specs 5w-50.
In the US CAFE is in the mix not so with other countries where it is NOT spec oil.
So it would seem the 5.4 modular can run on anything from 5w20 to 5w50 and anything in between.
I see you are running 0w20. Does your owners manual spec 0w20? What happened to specs or is that just for other people?
There is more to this than just a myth and I think that Ford might know a thing or two about their engines since they designed them--a 50 grade oil is not for that engine and nothing heavier than a 20 grade is needed--wanted or desired is something else entirely.
There is nothing more to that myth, its just that and nothing more or less. Obviously they designed that engine to run on more than on one grade of oil. Proof? Ford GT500 5.4L specs 5w-50.
In the US CAFE is in the mix not so with other countries where it is NOT spec oil.
So it would seem the 5.4 modular can run on anything from 5w20 to 5w50 and anything in between.
I see you are running 0w20. Does your owners manual spec 0w20? What happened to specs or is that just for other people?