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Front end noise

Discussion in 'Gen 2 Prius Main Forum' started by DigDoug, Mar 8, 2018.

  1. DigDoug

    DigDoug Junior Member

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    Just today on the way home from work I noticed a squealing noise or rather sounds like metal on metal. Popped the hood and noticed the brake fluid was low but not lower than the low line on the reservoir. Any ideas? Also noticed that the mobile app is not working any way to get the replies on my phone?
     
  2. Raytheeagle

    Raytheeagle Senior Member

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    Some questions:
    • Could it be the brake pad squealer?
    • When was your last brake inspection?
    • How thick were the pads?
    Hope that helps(y).
     
  3. DigDoug

    DigDoug Junior Member

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    I thank you for the quick response, last inspection was sometime last year, pad thickness I cannot say but they were replaced sometime in the last two years. I do not have the thickness in front of me since they(report from dealer) are in the car. Wife just called and said after going on an s curve nearby the noise stopped. I guess unless someone comes up with something else I will take my morning nap and see what transpires. Thanks for the help Raytheeagle.
     
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  4. Raytheeagle

    Raytheeagle Senior Member

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    Could also be something got lodged in the tire or brake area.

    Gone for now at least(y).
     
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  5. MickyMatter

    MickyMatter Active Member

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    If your brakes were sticking sometimes or over a period, your disks and pads can get thinner in short time. Then the brake piston has to be pushed more out of its cylinder to press the pads onto the disks. The result is a lower level of fluid in the reservoir.

    And if the wear of the pads is too much, their indicator will get in touch with the disk. This contact is metal-metal resulting in a screeching sound.

    After braking, there is no direct force helping the pads to lift off of the disks. There are only the disks, moving a bit <-> axially, while they aren't rotating perfectly. This causes the pads to lift off some micrometers. While driving curves, this effect is bigger, because then axial forces from the tires affect the disks, too.

    That's my theory. If your pads (and perhaps disks, too) are too thin, new ones could help. (Maybe the brake saddle is sticking, too and its guidance pins should be cleaned at least.) If they are okay, your problem is another one.
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    Could be they replace pads but have haven't been keeping up on relube of the caliper pins? Was it dealership?
     
  7. DigDoug

    DigDoug Junior Member

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    Well after this morning it is a moot point, I was hit today on the passenger side front end. Car is at the body shop for a while now. Dang that stinks.