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Clunk sound from front brakes when backing up

Discussion in 'Gen 3 Prius Main Forum' started by co_prius_3, Sep 6, 2015.

  1. co_prius_3

    co_prius_3 Member

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    I just had the left front strut replaced by an independent shop. Afterwards they noticed that pressing the brakes after backing up produces a single 'clunk' sound from the front. Not sure if it's from the left or right. Also not sure if it was doing this before the repair and didn't notice, or it just started.

    I've read that this is normal, but wanted to see if anyone else has heard this sound. It only happens once, although I haven't tried backing up twice in a row.

    Edit: sorry should have put this under maintenance. Mods, please move it.
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    If it just started happening after a strut replacement, my complete layman's opinion would be it's NOT normal. Bolt loose at top of shock tower??
     
  3. co_prius_3

    co_prius_3 Member

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    There's no noise or vibration on the road, so I doubt it's a loose bolt. I've read that it could be the brake pad shifting in the caliper after braking in the opposite direction for the first time. Another opinion was that the driver side brake clip was installed backwards. I guess I'll take it back and have them check it out.
     
  4. ChapmanF

    ChapmanF Senior Member

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    First thing I'd check would be the installation of the "fitting kit" clips (those shown in box "04947" here). The clips aren't all identical, there's a definite upper and lower one for each side. (If you look closely enough, the upper one has a slightly more prominent springy part: it pushes the pads normally toward the lower clip, the position that should be clunkless when driving forward.) Before checking closely that the clips were reinstalled right, sometimes you find the problem just by checking whether they were reinstalled at all. :)

    I just noticed something I never knew before: apparently since October 2011, they've been adding a little $0.77 bushing on the lower slide pin (see the part with the little "note 1" symbol in the caliper drawing, and also in the 04479 rebuild parts kit). I wonder what that's about?

    -Chap
     
  5. Ltlg

    Ltlg Junior Member

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    I heard this noise after I had one of my tire rotations. Brought it back to them and they said it was normal. Just the pads "adjusting".