No, it will not void the warranty. Dead Link Removed The only way a manufacturer can refuse to honor a warranty repair is if they can prove that the modification you made to the truck caused the failure. This is law.
Of course, some dealers are jerks about it. Luckily, most Ford dealers are pretty cool. Be happy you don't have a GM product. Dead Link Removed
Gloria
93 EB Explorer (highly modified)
94 F150 Lightning