As a testament to how horribly shitty dealers can be, this just happened in the last month:
My mom's Mercury Milan was making some very weird noises - loud metallic squealing. Ford dealer diagnosed the issue and found one of the rear rotors was scored and replaced it. Noise came back immediately on the drive home. Dad took it to the local gas station mechanic and they found the rear axle literally broken in half. The broken stub was resting against the fuckin rotor and damaging it. Dealer didn't say a damn thing (didn't even replace the brake pads
), and there's no possible way they didn't see the problem during the rotor replacement. In fact, the local mechanic suspects the dealer had to force the axle back in order to install new rotors and that likely caused more damage when they drove off the lot after the so-called repairs were done.