the sill strips that run along the inside visible ledge of my c180 have lifted and appear to have rusted inside...is this normal? i had a golf vr6 that had the same type of strips (difficult to describe) that ran along the outside of the car and they lifted away from the body and clipped off and were rusty. is this the same thing happening again if anyone is able to tell from my poor description? if so can they be easily replaced at relatively affordably? thanks.