There is something else you need to look at. In Canada, corrosion is a severe issue, and putting a non-sieze compound on the wheel hub and disc face is standard good practice. However, the aluminum of the caliper corrodes around the bushings that the pins slide on, causing restriction to movement, so that the brake caliper does not move freely. This can cause you to chase an issue with the disc, and not find the solution. There are 2 bushings, you can knock them out, clean the caliper holes with a round wire brush, and install new bushings with lots of silicone grease. There is a soft bushing and a harder one, make sure you note which goes where.