Squeal or tinny sound from brake system

MCIOCI

MEMBER
2008 HUMMER H2
6.2L
V8
4WD
AUTOMATIC
56,000 MILES

Has nothing to do with my physical brakes because noise happens even without pressing brake pedal. you start car and you hear it. when you first move truck and put brakes on you will hear it but as you drive you don't hear it again. I replaced master cylinder, accumulator, whole system ($1,000.00) and I still have the issue. Someone told me its the hydro-booster but the 2008-2009 H2's do not have this hydro-booster anymore. here is a link on this site with another member having same issue but I don't see any fix for it. took it to dealer and they had no clue.

https://www.2carpros.com/questions/hummer-h2-2008-hummer-h2-brake-noise-heard-when-braking#last

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,709 POSTS

Hi,

Is it only associated with tire rotation? I ask because you said you hear it when you start the car. Are you sure the backing plates behind the brake rotors isn't rusted or bent and touching the rotor? Also, there are indicators on the brakes that are designed to make a noise to indicate bad brakes. One could be bent and touching the rotor.

Let me know. Also, you mentioned hearing it when you press the brakes. Let me know if it does it with the brakes off, on, and if there is a change in sound between the two. Also, does the sound change with vehicle speed? Is there any change in sound when turning or anything you can think of?

Take care,
Joe