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Is it safe to use B while the car is still in motion?

Discussion in 'Gen 2 Prius Technical Discussion' started by Jaqueh2, Jul 1, 2007.

  1. Jaqueh2

    Jaqueh2 New Member

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    Because my friend actually stopped the car in mid drive and then put it into B and then started driving. He said that it would break the transmission, but i said B isn't related to the transmission... Clarification?

    Also when u guys had to replace tires, did u use new tires or the same economic tires that allows better coasting? because i expect tires with more grip to really show the true power of the wimp called Prius. Does B help in uphill drive or is it just a brake?
     
    #1 Jaqueh2, Jul 1, 2007
  2. Bill Merchant

    Bill Merchant absit invidia

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    B mode is for engine braking going down big hills. Small hills, up hill, don't bother, it does nothing good and wastes gas unless you need deceleration. The "shifter" is electronic, so you can't wreck the "transmission"; you can shift it to Park at high speed and it just beeps at you since that's nuts.

    MANY thread on tires. Many think the OEM Goodyear Integrity tires handle poorly in wet and slippery conditions. They are 855 revolutions per mile, so a replacement tire should be close to this to keep speedometer and nav accurate. 195/60R15 is about the same circumference.

    Welcome to PriusChat!
     
    #2 Bill Merchant, Jul 1, 2007
  3. mmoncur

    mmoncur New Member

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    It's far from a normal transmission. I shift from "D" into "B" at freeway speeds (only coming down a mountain, of course) with no trouble, and I've found I can flip from "R" to "D" after coming out of the driveway without bothering to stop the car completely. The Prius knows what it's doing. :)
     
    #3 mmoncur, Jul 1, 2007
  4. 8AA

    8AA Active Member

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    Not only can you shift to "B" while in motion, it's a great way to test your regeneration technique when stopping at a light. Ideally you'd want to use the friction brakes as little as possible, but sometimes you need to brake a little harder than normal. While you're braking, and after the car has slowed to 20 MPH or less, flip the lever to "B." Under 21 MPH the Prius will not use the engine for braking, but will engage the maximum regeneration. If you feel additional drag after switching to "B" then you could have been braking harder without using the friction brakes.
     
    #4 8AA, Jul 1, 2007
  5. richard schumacher

    richard schumacher shortbus driver

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    <div class='quotetop'>QUOTE(Jaqueh2 @ Jul 1 2007, 01:33 AM) [snapback]470939[/snapback]</div>
    Your friend should read his owner's manual. Stopping just to shift into or out of B is a waste.

    B does not help going uphill, except *possibly* for lead-footed drivers on slippery slopes when it might cause the limited slip function to engage a little less often than it would otherwise.
     
    #5 richard schumacher, Jul 1, 2007
  6. hobbit

    hobbit Senior Member

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    D, N, R, and B are just electrical suggestions to the computer. The
    only time anything mechanical changes in the transaxle is P, when
    a pawl engages a gear and locks the wheels. And the car won't even
    let you do that at any appreciable speed.
    .
    http://techno-fandom.org/~hobbit/cars/b-mode.html for much more
    information on this...
    .
    _H*
     
    #6 hobbit, Jul 1, 2007
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