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Front brake pads

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by james909, Dec 12, 2019.

  1. james909

    james909 Junior Member

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    For my annual inspection I got a warning that my front pads are wearing thin. What do you think?
    20191212_113744.jpg
     
  2. oldtechaa

    oldtechaa Active Member

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    Can't really see them from the picture. What do they measure? I believe 2mm is the replacement thickness.
     
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  3. Mendel Leisk

    Mendel Leisk Senior Member

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    upload_2019-12-12_7-44-23.png

    Yeah, well focused picture, of the brake rotor top edge. It is tough to get a decent pic.

    That said, I can discern the brake pads in the distance, looks like 4~5 mm? One millimeter is minimum thickness, but if they were 2 or even 3 mm, I'd be getting antsy.
     

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  4. james909

    james909 Junior Member

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    Thank you. I thought the same 4-5 mm. I have a focused picture of the other side. 20191212_113919.jpg
     
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    Seems like excessively wide rust zone on the rotor face?? First pic seemed like that too.
     
  6. james909

    james909 Junior Member

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    True but it's outside of the brake pad contact area. It's because of the salt on the roads in winter.
     
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  7. Mendel Leisk

    Mendel Leisk Senior Member

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    Ok. Yeah hard to judge the scale. If pad's not running on that zone, n'mind.
     
  8. ChapmanF

    ChapmanF Senior Member

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    Those rust bands at the inner and outer rotor edges just keep growing, and carving away the pads like so:

    rustband0.jpg rustband1.jpg

    It never stops being technically true that it's "outside the brake pad contact area", but only because the brake pad contact area keeps getting smaller as the top and bottom edges are carved away. :)

    It's not so easy to see how far along it really is, without taking the pads out for a look-see.
     
    #8 ChapmanF, Dec 12, 2019
    Last edited: Dec 12, 2019
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  9. james909

    james909 Junior Member

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    The rust band isn't as wide as it looks in the pictures. I think the angle has distorted it. Front on it doesn't look so bad but I get what you are saying. If I change the rotors it will start rusting again. I occasionally do a high speed friction brake in neutral to clean them.
     
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  10. oldtechaa

    oldtechaa Active Member

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    Your pads look fine. I'm at about 2 mm myself, and I'll probably change next inspection in 5k, maybe 10.
     
  11. dig4dirt

    dig4dirt MoonGlow

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    I would say spring time if not sooner, def think about changing everything out. pads and rotors
    Those rust zone probably keep traveling into the pad and soon wont be enough for a hard emergency stop, possibly

    The neutral braking is helping, but they may be too far gone to have complete surface contact
    and pads may even start chipping/chunking off if not already
     
  12. George W

    George W Active Member

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    In the mid 80's, German's were using dried pig piss to melt ice because they were concerned about salt corrosion. I thought it might be adopted in the States.
     
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  13. ChapmanF

    ChapmanF Senior Member

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    Isn't it a shame how much thickness is left on the pads in #8, everything fine except for the carving?
     
  14. Kenny94945

    Kenny94945 Active Member

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    OP got a warning?
    Verbal (or written) warning from an inspection station employee or dash board warning
    If employee, take "with a grain of salt" as I would disagree.
    If dashboard I would pay attention and agree.

    To my eyes, from the picture; pads look okay.
    Note the center wear grove in post 8 photo as a positive replacement point of wear guideance.
    I am unsure if 1 mm or 2 mm is the recommended remaining pad thickness, before replacement.
    Calipers et al sure could use a cleaning and probably the pins re-greased.

    Again from photo, pads "have some meat" left and appear okay.