[sourdough]

The Darco lining over the wheel wells has always been "weak" to me. It works fine, I think, if you only hit water on the highway. I can't imagine trying to run rocky roads with the Darco as the only lining I had.

If you've run 50k miles I figure you are really lucky that something worse hasn't happened. I would take it in and have it repaired professionally. I don't think that you can put anything on the tires to stop the throwing of debris into the wheel well. With the "cheap" underlining of the wheel wells and bottom (coroplast) you have to look at those lining often.