I've got a 06 crv ex fwd. Last year I was driving home and had an awful sound from the back. Basically the drivers side rear brake pads were completely to the metal, but the other side looked brand new. So we changed the pads and the drivers side caliper assembly. Now it did it again with the same wheel. The shop says the piston is depressing correctly and they say that it should be working just fine. They replaced the rear brakes again btw. Well after doing the brakes and aligning it it is still pulling to the left and I'm hearing a short squeak when I step on the brakes. Anyone have any ideas why that side could be hanging up?

 

Brake hose can be acting as a one way valve?
Brake line is pinched?
ABS unit not functioning correctly?
Master cylinder not retracting properly?

Yeah, they are all a bunch of wild guesses.