ChargedSolara wrote:rolling the rear fenders is shaving some of the inside of your rear fender, specifically the area that rubs against your tires when you hit a bump/dip in the road. this cost me 50 dollars at my local shop, and it reduced a lot of rubbing in the back, however with more than 2 total passengers my car will still rub, perhaps it has to do with the offset of my 18's, and i'm running 235/40/ combo as well.
What you're describing is called shaving the fender, not rolling. It has the same effect, though.
There is a lip inside the fender, where the sheet metal is folded inward. That is what usually rubs against the tires. You can either shave it, as Charged Solara just described, or you can roll them by having the lip bent upward, inside the fender wall, so that it doesn't protrude into the wheel well so much.