I found this chart on the Internet. It lists oil grade, oil capacity, and filter type for all Ford engines over the last 10 years. Might be especially handy if you need to do an oil change for a friend or family member.
My 7.3L is (and is supposed to be) running 15W-40, and the chart doesn't even mention it in Note 3.
So much for one hand of Ford knowing what another hand is doing.............
I suspect they meant to put a Note 4 by the 7.3, as that would make far more sense.
Not sure what you mean...the 7.3 is listed in the engine category where 15W40 is the primary oil in the heading at the top of the category. The footnote shows alternate weights for low temperatures. Does that make sense?
The chart is organized grouping vehicles with the same primary oil weight.
(My '91 BMW 318is spent most of its life on 15W40 Rotella--the primary recommendation--until it became a garage queen; I now put 10W40 in it for easier winter starts. But for cold temps the manual does show lighter weights as being allowed.)