I just put my 18" wheels on my 2007 Mazda a week ago. I just noticed that my fender bent inward a little bit. I'm not sure how it happened, but my pops is telling me that the tires are too big. My tires are 235/40/18. I know the recommened is 225/40/18 but thats all I have right now. Also it only happened to one fender and that wheel actually has a 245/40/18 tire on it. I know, I know, this is a problem, but how could the tire bend the fender outward? I was told that when the car hits a bump it can catch the fender and pull the fender out. Hard to believe. But, if this is a serious problem, I do have another 235/40/18 tire, so should I go ahead and change the one off sized tire? Also, is it dangerous to drive with one off sized tire? Its only one size wider...