Im positive it has to do with weather. Although this truck has only been in Alaska for about 3-4 years per the car fax, weather in Alaska is like no other when it comes to harsh conditions on vehicles. People on the island I live on also say that volcanic ash has a lot to do with corrosion of vehicles here and if you drove around here for a month you would see what im talking about. I make sure to keep my jeep clean as much as possible and during summer I try to get a few good coats of wax done and one more before the winter to avoid my paint getting destroyed. I will be working on the Tahoe this summer getting all the paint chips, scratches, and crudd fixed. A lot of buffin and waxin in my near future.