Brake not working

2004 CHEVROLET AVALANCHE

116,000 MILES • 4WD • AUTOMATIC

CHEVYNATION

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Okay. so, I have brake fluid in the cylinder not milky a little dirty maybe, but my brakes go to the floor. no leaks that I see, but when brakes are applied there is hissing.

May 31, 2022 at 5:56 PM

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SQM

AUTOMOTIVE REPAIR CONTRIBUTOR
6,383 POSTS

Hello,

There are a few different reasons why the brake pedal can go to the floor.
It could be due to air in the brake lines, leaking brake fluid, faulty master cylinder, it can also be due to low fluid level.

Here is a helpful guide:

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

Are you able to tell where the hissing noise is coming from?
Is it around the master cylinder?
Hissing noise is usually caused by air.

Let me know of any questions.

Thank you.

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May 31, 2022 at 7:28 PM