I'm not positive how many miles are on them, I've only had them for a week, There is some noise when you go over a dip in the road or something like that, I was thinking its cause the springs aren't for an lt1 car, so they sit lower on my car than they would on an LS1 car. But like i said I'm not positive on the miles, Also my tire rod ends and hubs are bad on my car so that helps make a little noise also