Q: Hissing and squealing when releasing brake pedal

asked by on January 25, 2016

I think the brake power booster might need to be replaced. i can hear a high-pitched hissing or squealing sound when I release the brake pedal.

That is the sound that the brake boosters will make as the seals for the diaphragm are worn out. I would recommend having a certified technician come out and determine if that is in fact the problem you’re having and replace the brake booster as needed.

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