Rear Brake Issue

Discussion in '5 Series' started by Oldbrook, Oct 30, 2019.

  1. Oldbrook
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    Oldbrook Site Supporter

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    Hi all, my 5 series GT F07 has a problem with the rear brakes, when I brake lightly the rear off the car seams to bounce up and down. I have replace the rear discs and pads and had the rear wheels balanced and still the same. Has anyone any ideas as to what this could be. Many thanks Dave
     
  2. Wynne71
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    Have you checked the rear shocks and springs? Possible snapped spring or two might cause similar issues.
     
  3. Oldbrook
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    its on air at the back but I did wonder if it was something to do with that
     
  4. slim_boy_fat
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    slim_boy_fat WARLORD Site Supporter

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    When you're braking "lightly", surely the majority of the braking effort comes from the front? Any 'oscillation' there could be transferring to the rear of the car, causing it to look as if that's where the problem lies.

    What are the front discs and pads like? Just a thought.......:oops:
     
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  5. Oldbrook
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    Hi fronts look ok and no shaking of the steering wheel but I can feel it through the seat. Dave
     
  6. Peter
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    Peter WARLORD Site Supporter

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    Similar thinking. I also wonder if the Electronic Brake Proportioning (EBV) could have an issue, pulsing at light braking loads to generate the sensation.

    Peter
     
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  7. Oldbrook
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    Hi Peter, that sounds possible, would that show up if it was plugged in to diagnostics, Thanks Dave
     
  8. Peter
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    Peter WARLORD Site Supporter

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    It's possible it could have logged a fault code, but can't be sure, particularly if it is a EBV valve issue.

    Just a thought, are you using OEM tyre sizes front and rear? Reason why, wheel speed front to rear is involved with Electronic Brake Proportioning.

    Peter
     
  9. Oldbrook
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    Oldbrook Site Supporter

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    Hi Peter, yes to tyre size, car has been in my local specialist and they are saying it wants front discs and the track control arm bushes have de laminated causing me to feel vibration through the seats. No shaking of steering wheel so not sure if this will cure it and the cost is just over 1k, a lot of money if not cured. Dave
     
  10. Peter
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    Peter WARLORD Site Supporter

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    That is a costly one to try. Front is not normally felt primarily through the seats/body, but is possible.

    Peter
     
  11. Oldbrook
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    I don't know how I would stand if it was still the same as I have asked them to diagnose and repair the problem. Dave
     

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