Finally identified exactly what this part is...

[rumblecloud]

I kinda knew what these were, but did not know for sure what they were called or where exactly they were positioned


They are Fender Insulators, part number F37Z 16K171 A.
Now I can sleep at night

 

[lostranger2026]

Thank you! It's a year after your post and I had exactly the same question!
I found mine crumpled up when I took the fender liners off and in all honesty, I still can't see how they're supposed to go back on. It looks like it's supposed to go flat again the wheel chassis panel, door side. I really don't see how that would work though. Did you ever manage to figure it out?

 

[JoshT]

Goes between the fender and the cab structure to help block air flow through there. Probably a part of Ford's NHV solution on these. Really doesn't seem necessary. The ones I've seen when removing fenders appeared to esssentally be held in place with double sided tape from the factory, probably primarly for installation then friction does the job once fender is in place. .

 

[rumblecloud]

Thank you! It's a year after your post and I had exactly the same question!
I found mine crumpled up when I took the fender liners off and in all honesty, I still can't see how they're supposed to go back on. It looks like it's supposed to go flat again the wheel chassis panel, door side. I really don't see how that would work though. Did you ever manage to figure it out?

Did figure it out, but did not reinstall. I may revisit if I ever pull the fenders again.

 

[PetroleumJunkie412]

Hey @Blmpkn ,that's what those chunks of foam in the cab are. I couldn't remember, either.