A squeal from the front of the car isn't automatically a pad problem, and a grinding noise isn't automatically a rotor problem. Here's how to actually tell them apart before you pay to replace both.
The squeal
Most brake pads have a small metal wear indicator built in on purpose — it's designed to squeal against the rotor once the pad gets thin, as an early warning. It's normal, it's not damage yet, but it means the pads need attention soon, not urgently.
The grinding
Grinding is different: it usually means the pad material is completely gone and you're hearing metal backing plate on metal rotor. At that point the rotors are very likely being damaged with every stop, and this moves from “schedule it” to “book it now” territory.
The pulsing
A pedal that pulses under braking, or a steering wheel that shudders, is almost always a warped rotor from heat — not a pad issue at all. New pads on a warped rotor will still pulse.
Resurface or replace?
Rotors can sometimes be resurfaced — machined flat again — if they're still above the minimum thickness stamped on them. Once they're below that minimum, or badly grooved, replacement is the only safe option. We measure before recommending either one.
Brake service (RR‑9) covers pad, rotor, and caliper inspection in one visit, and we show you the actual wear before anything gets replaced.