High pitched noise when brake applied at idle

Hey everyone,

Anyone have any ideas what could be causing this noise? Seems to be a sweet spot on the brake pedal. Happens at idle and when driving. Check out the video and let me know what you think. Thanks!

https://youtube.com/shorts/IjQqHe_O63Q?feature=shared

 

Brake booster is failing and leaking vacuum, before replacing pull the master cylinder back and make sure it isn't leaking brake fluid into the booster.
If it is you need to replace both, if it's not you can just replace the booster.

 

Weirdest Video Ever
But perfect

as DM93 states….has to be booster bc of weird vacuum leak sound
Really good advice to check if brake MC leaking into booster as well


There are vids out there that show how to test booster
Videos take longer to watch than to test actual truck’s booster (super easy test)
GL

 

Will you be doing the work or ?

 

Thanks for the input everyone. I thought it might be the brake booster. My brake light also started coming on and off when I brake harder. That was a newer addition to the problem this week.

Yes, I’ll be doing the work this weekend now that I have time to get this on the jackstands.

 

You do not have to take the brake master cylinder off when doing this. You can gently persuade the brake hard lines forward enough as you move the master cylinder forward to gain clearance for removal. There is a seal in the front part of the brake booster where the snout of the master cylinder slides into. You might have to transfer this from your old booster to the new. Be careful when you put the master cylinder back on. If you damage this seal you will have a vacuum leak and the subsequent codes related to a lean condition. The pushrod that projects from the front of the booster “should” be adjusted to the proper depth, Some people have experienced a click in brake application afterwords or the brakes dont “feel” right afterwards. 99% of the time it is a simple job, it is the 1% that makes you question your “mechanicing”.