The starter could grind if the bendix is sticking
Yes they can make a grinding noise, if they are bad.
What would cause a grinding noise after a tire is replaced and the brakes are not worn?
sounds like a bad starter gear or bad flywheel
Normally a rusty rotor would not make a grinding noise. A grinding noise from the brakes usually indicated that the pads or shoes are worn down.
You probably have something wrong with your engine, or brakes. You should really have that checked.
your barrins in the wheels
Mine did this, replacement of distributor solved the problem. Go figure?!?
why is there squeek noise when starting and then goes away when engine warms up
Running too lean.
I would guess that it is the wheel bearing. is it a grumbling sound or an all out grinding? If it is or was a grumbling sound and has turned into a grinding it is probably the wheel bearing.
bad rotors
Its kind of a grinding screeching metal on metal noise.