I have a 04 Lariat with 18” factory aluminum wheels and the wheel caps that have a gold colored (Arizona Beige) adhesive covering in the center of the caps. They are bubbling up and look quite ugly, and it seems to be from a corrosive action between the wheels and lug nuts; possibly from the contact of the aluminum and steel.
I experienced the same problem with my 97 caps, a green pitting like action that grew on the caps, only 2 of them as a matter of fact and never did figure out a fix or cure, just replaced them.

Anyways, has anyone else seen this and have you tried to clean up or repair their caps by either paint or applying an adhesive covering to the caps. I thought about getting some vinyl, like what is used for graphics and etc… possibly black, and covering the center of the caps for a cheap way of repairing an unsightly area of my truck.