Our car has only about 22k miles on it, but it's always been kept outside (in NY) and went for several months this winter with no use. This summer, we developed a low grinding sound when braking. A visual inspection shows there's still a lot of brake pad left, but the rotors are seriously scored with grooves and rather rough to the touch. The rear ones are worse than the front and the sound seems to be coming from those. My question: should I just live with them as they are until the rough rotors wear the pads down and then replace everything, or should replace the pads early and get the rotors ground?
If the pits are really deep, then grinding may not be an option - there is normally a minimum thickness specified.
I would suggest that you save up for the new pads and rotors and change them when ready. That is ONLY if the existing ones are stopping the vehicle as they should - a bit of extra noise is not an issue as long as the stopping power is there.