Yesterday I started to get a high pitched sqeal from my drivers side rear brake. It goes away as soon as i tap the brakes. Is their a low pad warning mechanism on the 01 Blazer 4wd? Brakes work fine. I changed the front brakes last summer. Have not done rear. 123000 miles.

 

123K? why wait any longer? pads don't cost much, rotors do.

 

i would suggest relacing the pads.. nowadays pads have SQUEALERS on them to tell you that the pads are gettin low before they damage the rotors... also there is a drum brake inside of the hub of the rotor for the e-brake i suggest pulling off the rotor and checking it too for anyhting loose/missing or bad

 

So I replace rotors and pads and today I hear a rhythmic knocking from the passenger rear brakes when it is in motion.. It comes and goes but does not change when I apply the brakes. It brakes perfectly. I even here a slight squeak. Any ideas what might be causing this.

 

these blazers have internal emergency brakes inside the drum of the rotor (i know sounds crazy) these are notorious for having the pad come apart from the shoe. if you pull of the rotor you'll see what im talking about and these are just cable operated so know worries about brake fluid