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Switching to rear disk brakes??

Discussion in 'Gen 2 Prius Main Forum' started by BT Tech, May 7, 2005.

  1. tomdeimos

    tomdeimos New Member

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    Brake fade used to be a common and scary problem in cars. I don't see any issue where the car has disks on the front wheels though. Should be much easier to stop than in a Saab with free wheeling and 4 drum brakes that got too hot. Even with the free wheel locked out brake fade was a problem in the rockies. I remember making regular stops just to let the brakes cool.

    The other big problem with drums was in flooding when they got very wet. Again having disks at least on front wheels should help a lot.
     
  2. Orf

    Orf New Member

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    Test on all sorts of cars over the years have shown that disks are superior to drum brakes. Why would the Prius be any different?
     
  3. IsrAmeriPrius

    IsrAmeriPrius Progressive Member

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    <div class='quotetop'>QUOTE(Orf @ Nov 11 2006, 04:45 PM) [snapback]347611[/snapback]</div>
    Because the bulk of the braking on the Prius is done by the regenerative system and not by the friction brakes. That keeps the brakes cooler and thus less prone to fading. The major advantage of disk brakes over drum brakes is resistance to fading. Fading is a minor issue with the Prius brakes.
     
  4. ncc74656m

    ncc74656m New Member

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    FYI guys, I can tell you from experience that you WILL need a different proportioning valve without question. As to the ABS, I am not entirely sure, but I wouldn't really want to mess with that without being SURE.

    (Yes, I know it's an old thread, but it seemed like a worthwhile response to add)
     
  5. Georgios

    Georgios Member

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    After reading this Old thread i looked up some german sites and found that the european prius also has drum brakes..partially. They are DRUM + DISC - unbelievable. In the link below you can see front + rear brakes replacement and you will see the pictures down with the rotor that plays role of the drum.
    We all know the rear drums barely work hard and now i realise that having a caliper helping the car stops is a truly overkill.
    I really want to have disc brakes on my car.
    I dont care about fade or stopping distance as there were big debates even involving Tundras and GMCs. Fade is never a problem for the prius daily use
    I just want to do it for the look of it. Discs always looked better to me. Thas all


    Soon I will be going to Europe for 1 month and i will look and i hope to find some prius and see whats exactly the difference between the structure aroung the rear hub. Mainly where does the caliper gets feed with brake fluid

    Bremsscheibenwechsel – Prius Wiki

    IMG_20170417_131554_fr2.png
     
  6. RobH

    RobH Senior Member

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    The drum is the parking brake.
     
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  7. Mendel Leisk

    Mendel Leisk Senior Member

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    More like common place. That the setup on a lot of cars: rear disc brake plus a mini-drum in the middle to function as parking brake. I've worked on a 2010 Honda Pilot that has that.
     
  8. Georgios

    Georgios Member

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    Ah, i didnt think about the parking brake...you are righ, its for that reason
    I normally see 2nd caliper just for the parking brake on some cars that have monoblock calipers on the rear.
    This swap is probably mission impossible to change the drums to disc without a donor car side by side
     
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  9. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah not worth it.
     
  10. jimolson

    jimolson Member

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    I would be concerned that installing disks and rotors on the rear wheels would alter Toyota's informed choice of front/rear proportioning of braking.

    You will have no knowledge of the fluid pressure vs. braking force of a disk brake retrofit. It's possible that Prii sold in the US and equipped with rear disks have their proportioning valves designed differently from North American vehicles.
     
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  11. Georgios

    Georgios Member

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    Obviosly. Both systems needs to be examined carefully and then will be claer whats what. Normal european owners are sunday drivers and i am surpised no one has ever got to it with the large number of cars.