Grip Strip
 

I just had my rear door "Grip Strip" replaced under warrantee. Seems one of the plate lamps wasn't working and when the dealer checked, the insides of the lamp assemblies were corroded. They decide to just replace the whole "grip strip" as they call it. Took 15 minutes after they finished painting it. Has anyone else had this trouble? And any idea how moisture got into that area of the vehicle? I realize it is an area that is sometimes exposed when open, but it seems like the rear doors are very well sealed when shut.

Thanks. 2004 4.4 47,000 miles