Eastwood now makes a pneumatic fender former that is even easier to use then a fender roller. If your wheel or tire contacts your fender due to lowering springs or larger wheels and tires, this is your fix.
As long as you can fit this tool between your tire and fender, you won't even need to remove the wheel. Using a fender roller takes more time and only has one use. This fender former is also great for crimping door skins and straightening bent edges.