I know this is a highly contentious question and I am bound to get a number of answers about turning rotors at every pad replacement, but this is going to be a simple replace or keep question as I don't like turned rotors.
I have had a brake pad wear all the way down to metal and it has scored the inside side of the rotor (front drivers side VX Commodore if that makes a difference). Now I am replacing the pads in four days when I can get to the auto shop, but am needing to work out how critical it is to replace the rotor as well. It is definitely scored and it can be felt and seen (compared to the smooth outside side of the rotor). Now I have been struggling to find any firm advice on this online, with some sites saying the new pads will bed in and mate with the rotors even with scoring, others say rotors should be turned every pad replacement, and others still say any damage at all should be turned or replaced.
My question is how much damage (i.e. how deep the scoring is) needs a replaced rotor (no turning replacement or keep only).
Additional #1 When I checked the pads to begin with I found that the rotor was sitting loose on the axle and that all that was holding it in place was the wheel and that with the wheel being removed the rotor could move a fair bit on the wheel bolts and was only being retained at that point by the brake caliper. Is this normal for the VX Commodore or should the rotor be attached through additional screws or bolts.