Hi, I could hear the humming sounds from my brake cylinder/booster from the cab frequently, is this normal?
Below are the cases/timing of my brake cylinder/booster making sound:
1. when I have a long time did not start the truck then I start it and flooring the brake, for example, the truck sits in a garage overnight, I can hear the sound when floor the brake panel and I start the truck the next morning.
2. after hit the brake many times, let's say after keep hitting the brake 5 to 10 times, it starts to humming
3. when I hold my foot on the brake panel for couple mins, for example when I wait for a red light, it will start humming some time.
And the sound not that loud but I can clearly tell when it starts and stop. The brake always working well, just the sound. And it is LC100 2004.
Is this normal? or means there is some issue with the brake cylinder/booster? Thanks!
Below are the cases/timing of my brake cylinder/booster making sound:
1. when I have a long time did not start the truck then I start it and flooring the brake, for example, the truck sits in a garage overnight, I can hear the sound when floor the brake panel and I start the truck the next morning.
2. after hit the brake many times, let's say after keep hitting the brake 5 to 10 times, it starts to humming
3. when I hold my foot on the brake panel for couple mins, for example when I wait for a red light, it will start humming some time.
And the sound not that loud but I can clearly tell when it starts and stop. The brake always working well, just the sound. And it is LC100 2004.
Is this normal? or means there is some issue with the brake cylinder/booster? Thanks!