The truck probably has a roller cam so the chance of a flat cam is nil. No more flat tappet cams anymore. Old, non roller engines relied on windage to lube the cam, not so on modern engines. As long as there is oil pressure, the cam and valve train are fine. Same reason they removed the zinc out of modern oils but that's a whole different argument.
They're other reasons Ford recommended not to idle modern diesels that don't apply to gas engines and has nothing to do with lubrication issues at low engine speeds
Idle away......
Adam
Prior Master Ford Tech 20 years experience.
