I bought some Porterfield pads for the front of my car, (05 C230K sedan), and I've changed brakes a million times just never on something with anything more then a piece of metal that scratches on the rotor when the pads are worn, lol. My question is this, can I just swap the pads without replacing the wear sensors or do those things have to be fresh with the pads? Hell, I don't even know what a "wear sensor" looks like. Sorry for the rookie questions but I'd like to know a little about what I'm jumping into before I go tearing into this car. My truck, pfffffft, we'll fix it later if we jack it up, lol.