Bob-o

I've been to all three major auto chains here in s.e. mi. and all sell the same type of new rear rotor. The problem I'm having is that when I install the new rotor and tighten it on with 2 lug nuts the inner side is contacting my caliper. I ruined the first new set in 2 miles of driving because all seemed well until I tightened the wheels on. This problem does not involve the new pads. Its metal to metal from new rotor to caliper mount. Has anyone else experianced this?