Help diagnose my brake sqeak
 

History: Brakes were fine, rear pads were low. Changed rear pads. Now the rear passanger side caliper squeaks when I'm driving, but it stops when I hit the brakes (or pull the handbrake a bit).

The noise isn't constant - as in it doesn't happen everywhere in the tire's rotation - only about 90 degrees of it (Measured by jacking the back up and turning the wheel).

I'm going to go grease up the rear brakes, see if that helps.

It's worth noting that the rear right caliper was in the worst condition - it was a bitch to get the pin out, had to hammer it once everything was disconnected because it was effectively seized on there.

I had a squeak that ended up being slightly bent hub. It sounded like a chirp chirp chirp while driving. It started as an infrequent chirp, then eventually became too annoying to ignore.

side note: If you arent sure if it is the hub or bearing, just replace both. The new $40 bearing won't survive if you have to pull the hub to replace it. Ask how I know ;)

I was just out greasing up the caliper pins and I noticed that no matter how far the piston is retracted (within reason), it grabs one part of the rotor and makes a slightly grinding noise. The rotor looks fine, but I only have my eyes

Oh, and something I've just remembered - the noise completely goes away when I brake.

Sounds like the hub after some research. Here is what I found:
Is this accurate? Because that is basically what happens to me, except I don't even have to push the brakes for it to sound like that.

If I replace one wheel hub should I be replacing the other?