157dB

The rust ring is normal.
Upgrading to GT rotors and GT caliper brackets is a good idea.
But for the cost conscious, I would mic the rotors and see how
close they are to the service dimention cast into them.
There is also a cut-out on the outer edge that shows how worn
the rotors are.
Deglaze the rotor surface and get some new pads and the
'worn out pad squeel spring' will stop squeeling.
Ford designed the pads to have a squeel indicator spring
when they are 80% worn out...
Bend the spring back and the squeel will disappear like magic.
Get ther pads replaced soon or your rotors surface will disappear
just as fast...

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