Are you talking about the door guards/moulding that runs horizontally down the sides about a foot or so up from the bottom of the door? I assume you are as this seems to be a common problem with our trucks. The clearcoat yellows and peels and the paint underneath starts to fade much much faster than any of the other body panels. The only choices to fix it right is to take it to a body shop that will repaint and clear the strips for you or just do what myself and a few others have done and take them off. I think it looks just as good if not better with them gone. Their only purpose besides appearance is to maybe keep your door from catching a ding but I park 40 miles from everyone else anyway so that doesn't really worry me.
There are a couple of different methods to get them off but it's not difficult. If you are interested let us know and we can give you some tips.
06-08 chrome clads w/33" Cooper Discoverer H/T Plus, Mopar tailgate spoiler, debadged door trim & tailgate emblems, 13" antenna, LED dome & maps, Magnaflow 22" SI/DO, 18% tint, "HEMI" hood spears, VHT tinted tails & third brake light, Lamin-x optic blue fogs, leveled w/McGaughys 2" drop shackles.