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High engine RPM going downhill

Discussion in 'Gen 3 Prius Technical Discussion' started by nedim, Jan 9, 2015.

  1. GregP507

    GregP507 Senior Member

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    I've never had that happen, even pulling a 6000 lb trailer. In fact it has a "trailer" button which provides more transmission-braking.
     
  2. DoubleDAZ

    DoubleDAZ Senior Member

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    I did and fortunately I had the oil changed right shortly after with no damage done.........lesson learned.
     
  3. GregP507

    GregP507 Senior Member

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    I remember the old Desi@Lucy movie called The Long, Long Trailer. They were pulling a giant Airstream through the Sierra Nevadas with a convertible as I recall, and I think I remember a scene when Desi had his foot to the floor as they crawled all the way up a long hill at a walking pace.

    I wonder how many transmissions they burned out shooting that scene.
     
  4. GregP507

    GregP507 Senior Member

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    Correction: It wasn't an Airstream.

    The LLT.jpg
     
  5. fuzzy1

    fuzzy1 Senior Member

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    Your dad was talking about replacing worn brakes, not handling a downhill situation where the brakes have overheated and lost their effectiveness.

    B mode is there for situations that have a risk of overheated brakes. If you are still using a bit of throttle here and there, then you are far from that situation.
     
  6. CR94

    CR94 Senior Member

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    Even if there are no faulty parts, water vapor from the atmosphere slowly permeates through seals and hoses into the fluid.
     
  7. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    One answer to 'why is there a B mode?' is that in the US, regulations require a gear position with more resistance than D. B mode satisfied the regulators. While it can be used well by a driver, you never need to use B.
     
  8. HaroldW

    HaroldW Active Member

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    Fuzzy1 , I. Only add a bit of throttle when I want to extend the glide. H
     
  9. fuzzy1

    fuzzy1 Senior Member

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    If you are extending a glide, then there is no imminent risk of overheating the brakes, so it is not the situation that 'B' is meant to address.
     
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  10. GregP507

    GregP507 Senior Member

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    No, "B" doesn't stand for "Back-up."
     
  11. HaroldW

    HaroldW Active Member

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  12. Qamar Fahim Khan

    Qamar Fahim Khan New Member

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    Recently i visited hill station, here one of the track is very steep and rough, on uphill it was ok but on downhill i engaged b mode but still speed was way fast due to steep, my question is how to control speed on such steep hills, i miss first gear of manual in these hills, please help
     
  13. bisco

    bisco cookie crumbler

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    b mode and brakes. have you considered a funny car parachute?
     
  14. Mendel Leisk

    Mendel Leisk Senior Member

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    In case you haven’t heard the expression; this is a funny car. ;)

    IMG_1364.jpeg
     
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