Sorry to hear that man. I do think that this is a common problem with Silver and White cars though. The paint never gets warm enough to drive out the moisture in the panels. That is why I like darker colored cars. But after only three years?? Not normal if it is as bad as you say it is. Talk to Ford for sure! Good luck man. My tour never had even a slight inkling of rust in 4 yrs, with heavy salt driving every winter.
