I've been dealing with this issue on my blazer for a while now. There is black plastic trim around my rear side windows that has gotten this strange texture on it (supposed to be completely smooth and black, but it's all pitted, and faded. I've tried dressing which helps with the discoloration for a while, but the pitting and what-not is killing me. I'm going to try and take pictures in a few once it brightens up a little bit. Any help you guys can provide would be greatly appreciated.