Originally Posted by
texastech_diesel
The cab may be close to being the same, butI'm almost 100% certain that the front part of the frame was redesigned for the 08 body style. Something about lower frame rails up front to help the truck not climb over cars in a head on collision seems right, I remember seeing some pre-production models where the parts of the frame there were changed were painted red so you could see the difference, but I can't find those pics anymore. So that means the bumper probably won't line up anywhere close to where it would on an 08, throwing off the grille, then the hood, etc etc. It could probably be done, but it's not going to be a bolt-on type deal.
The guy that does all my work on my truck has a salvage shop for Super Duties, and he chops and pieces together trucks all the time. I asked about changing my '03 front end to the '05-'07 body style. He said that in '05 all they changed (as far as the outside body goes...not talking about interior or suspension and stuff like that) was the front bumper, the grille, and the headlights. The bumper is completely interchangeable but to have the new grille you have to have the new bumper (because it dips down lower in the center). This means that to change the body of my truck from an '03 to an '05-'07, all I need is the new bumper and grille, an the headlights are optional. However, from '99-'10 the frame of the truck was COMPLETELY unaltered. That does not mean you can interchange all body parts from these years though. When they started the '08s they left everything the same from the front doors back, but changed all kinds of stuff like the grille, the front bumper, the hood, the mirrors, the headlights. Which means....if you're planning on converting between '08-'10 models and '99-'07 models, you're gonna have to do some fabricating because the mounting bolts for the bumper, the mounting for the grille, how the hood runs, how the headlights fit and some other stuff is very different. Hope this helps.
Oh, and the '08s did start doing that "Super Duty" thing on the bottom of the tailgate, and the driver side pivot for the tailgate is different, but I wouldn't technically consider this a body change.