If anything the rust will get worse. If you put those flares on it, you will trap moisture and dirt which will cause the rust to worsten. If you do decide to put them on, Putco makes a decent product, never heard of the other companies. Chances are your wheel well rusted from the inside out, which means you would have to cut the 1/4 panel and put some new sheet metal. The way to prevent that wheel well rust is everytime you wash the truck you should rinse the upper lip in the wheel well out. That lip is full of salt, dirt, and grime.
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