Hi, I have a 1985 Toyota 4x4 Truck. I just noticed if I have the parking brake on and i rock the truck back and forth, the back brakes make a noise. Its like a urrg, urrg noise. And also when my parking brake is pulled all the way my trucks tires still move. My parking brake is weak. I wanted to know if this noise is from the parking brake being weak and the brakes not griping enough. The noise is only when i pull the parking brake, if I have the parking brake off the truck will rock but it doesnt have the noise. PLease Give me some Info!!!!!!!!