I have a 2018 Mazda CX-5 GT that started having vibrations in the steering wheel during braking so I replaced both front brakes/rotors due to a warped rotor. I had 106,000 miles on the car with OEM brakes and wanted to keep the same quality. I purchased brand new OEM front brakes/rotors in march 2023 from a mazda dealership. The steering wheel vibrations went away and everything seem fine for a few days until I started noticing a grinding noise from the front driver side when I press the brakes a bit harder while going above 40 miles to a complete stop. It doesn't happen all the time and does not happen when I tap the brakes lightly or press on the brakes during highway driving. The grinding noise also goes away after multiple hard braking events once the brakes get hot but then the noise comes back the next day. The dealership added anti-squeak material on the pads which helped for a day but the noise came back. They then (supposedly) replaced both front brake/rotors as a manufacturer defect and there were no changes with the sounds still being there. Then they took it for a week long diagnosis and came back with not finding anything else wrong but noted that I had some rust buildup on the bottom of my vehicle and some rust on the calipers. They offered to replace the calipers for over $1000 with no guarantee that this would resolve the issue. They said the noise is not a safety issue and you can turn up the radio to not hear it. Since this grinding noise occurred after the new brakes were installed and I have no other symptoms of a bad caliper, I did not think it was a good choice for me to proceed with that option. Does anyone know what else could be wrong with it? Thank you!