Solve Suby Sound with me

[California98Civic]

My wife has a 2010 Subaru forester. It is making an intermittent squeaking sound of metal on metal from the rear drivers side wheel. It seems to be brake related. When I depress the brake the squeaking sound emerges. When I start again, the sound increases in intensity as the rpm of the wheel increase. But the sound disappears at about 20 miles an hour, only to return if I even tap the brake for a moment. My thought was that it was an indication that the brake pads are worn and that the sound is the metal tab squeaking against the brake disc. But then the sound sometimes goes away for a few days. And the last time I tested it, the sound didn't occur at all if I used the brakes traveling in reverse. That was weird. The Subaru is an all wheel drive car of course. I'm wondering if people think there could be something related to the differential for that wheel that is causing the squeaking.

Thanks for any feedback you can offer me. If I haven't been clear I'll answer more questions too.

[JockoT]

Have you done the obvious thing and checked the wear on the pads? Assuming you have, it could possibly be a stone trapped between the disc back plate and the disc itself.

[Frank Lee]

Here in the Rust Belt the first thing i'd do is pull the wheel and the caliper and make sure those guide pins are clean and lubed. Of course check pad and rotor condition. Retract the piston while you're there.

[California98Civic]

Both good suggestions. Thanks, guys. I only had time for a cursory inspection with the wheel on at first. Then the sound went away, so I left well enough alone. Then it oddly came back. It is still there and life is so busy I am procrastinating the further inspection. Better do it soon! I'll report back the resolution of it.

Thx!