I'm curious about this, recently I have noticed some of the Mustang magazines, ya I know this is the F150 page.... But they have been talking about the differences in the 4.6 Liter engines going into Mustangs. Apparently there are physical differences in engines built in the 2 plants supplying 4.6's to the Mustang assembly lines. Making it so some parts from one engine line do not bolt up to engines built on the other line. The lines are different plant locations, like Windsor and Cleveland. Just using those 2 as an example, because I can't remember what they magazines actually listed.

Does anyone on this list know if our 4.6's have the same situation?

 

Yes, the 4.6l engines in the F150's are slightly different depending on which engine factory they came from. The engines come from the Windsor Plant or the Romeo Plant. Differences are mainly internal, although I can't remember what they are off the top of my head.

 

In addition to what Gopher said, Not that it makes that much difference, but the valve cover bolt configuration is different, too.