Had a grinding noise coming from front passenger brake while out one day, so pulled in at a garage to have a look. Nothing wrong, pad looked fine, everything looked fine. Guy cleaned everything and put a little goop on the pads, has been fine since. Probably just caught a pebble or something. The guy said my rotors looked a little thin. At what point should they be replaced? And should I buy brand new, or find some thicker than mine from a junk yard? I've honestly never given a thought to my rotors other than taking them to be turned when I change the pads. Is there a specific thickness at which I need to replace them?

 

Some have the minimum thickness stamped on them somewhere near the lug holes. If they have been turned more than twice, i'd consider replacing them. The thinner they get, the more prone to warpage they are. Prices for new ones start around $25 on up. Because of where I live and the high gas cost to get rotors to a shop that can turn them(and then get back to pick them up), Lately I've just bought new.

 

I agree with floorslayer1, go ahead and change them next time and stay away from the bone yard for that. With the amount of rust and possible warpage they'll take off while turning they could be at or close to min. thickness. Autozone has good rotors for cheap, but I'm not a fan of their pads.

 

Stay with the premium pads when you replace your brakes in the future. The economy pads are garbage and cause rotor warpage and gouging from breaking apart. When it comes to brakes I always put on the good stuff.