rear brake grinding noise at low speed

Discussion in 'Prime Main Forum (2017-Current)' started by MarkOlin, Mar 29, 2020.

  1. MarkOlin

    MarkOlin Junior Member

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    My car has about 2000 miles on it. From day one I get a grinding noise from the rear brakes at speeds of 1 to 3 mph. Originally I thought the car might have some surface rust on the rotors but I get this noise all the time, even after a long commute.
    Is this normal?
    Thanks
     
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  2. bisco

    bisco cookie crumbler

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    not that i have read, have you returned to the dealer? maybe a dragging pad or e brake is not releasing all the way.
    or it might just be something in there rubbing.
     
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  3. ChapmanF

    ChapmanF Senior Member

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    Just to be clear, is the noise only there when you are braking?
     
  4. MarkOlin

    MarkOlin Junior Member

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    yes, only when braking and only at very low speed
     
  5. Rob43

    Rob43 Senior Member

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    I won't go as far as recommending a full "bedding your brakes in", but would suggest one medium/hard 50 mph to 2 mph braking event.

    Then let everything cool down, maybe your issue goes away.


    Rob43
     
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  6. sam spade 2

    sam spade 2 Senior Member

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    Since it is new and still under warranty, I would strongly suggest taking in to the dealer to have it checked out.
    Before you go, practice demonstrating the noise.

    Not sure it would be a good idea to make any "hard stops" if there might be something wrong back there.
     
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  7. bisco

    bisco cookie crumbler

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    no reply
     
  8. Rosanne Shalf

    Rosanne Shalf New Member

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    Same here. As long as it doesn't indicate a problem, I am not worried about it.
     
  9. PianoBench

    PianoBench Member

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    Generally if you are not experiencing vibration, the vehicle pulling to one side, or any unsafe abnormal vehicle behavior while under braking, I would not be concerned. The noise is occurring because there is rubbing somewhere between the brake pad and brake caliper system that holds the brake pads in place. When you are braking, there are shims and anti rattle clips between the brake pads themselves and the brake caliper that try to hold the brake pads steady and firm when under braking. Those skims and anti rattle clips just need to have some brake anti-seize applied to them. Pretty much lubricant for where those clips will come into contact with the brake pads and caliper.

    NOTE: YOU DO NOT PUT LUBRICANT BETWEEN THE BRAKE PADS AND ROTORS.

    Here is a good diagram that can help you understand what is going on.

    https://www.aa1car.com/library/disc_brake_floating_caliper_assembly.jpg

    Here is a good video on how to fix this problem yourself if it really bothers you.
    Edit: Its a 15 minute video. To jump to the most likely noise for your case, he starts around the 9 minute mark. Because your vehicle is new, it is most likely rubbing on parts that hold the brake pad in place that need to move as you depress the brake pedals.

     
    #9 PianoBench, May 11, 2020
    Last edited: May 11, 2020
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