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Discussion Starter · #1 ·
Is it bad to switch quickly from D to B if only for a few seconds while traveling at highway speeds, and then switch quickly back to D? I've found that when I see break lights ahead, I can throw the car into B and slow down enough to not need the brakes. Is there any harm in changing gears quickly and when traveling at higher speeds?
 

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The B gear is for if you want to slow the car down and the battery was already fully charged, like if you were going down a mountain and you didn't want to heat up the brakes too much.

Now if only there was some way to transfer all that wasted energy to the people going up the mountain in the opposite lane...
 

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Discussion Starter · #6 ·
what about when you're rolling up to a stop sign or you see a stoplight turn red up ahead? why not just shift to B and let it coast to a stop without having to wear down your brakes?
 

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CrosbyF said:
what about when you're rolling up to a stop sign or you see a stoplight turn red up ahead? why not just shift to B and let it coast to a stop without having to wear down your brakes?
It's not as efficient and you lose regenerative braking.
 

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CrosbyF said:
what about when you're rolling up to a stop sign or you see a stoplight turn red up ahead? why not just shift to B and let it coast to a stop without having to wear down your brakes?
Unless you are pressing on the brakes real hard you are not using the mechanical part of the brake. There is no brake pad contact until you get below 7 mph. What happens is the electric motor that drives the wheels now turns into a generator to regenerate electricity to charge the battery. When you are spinning the ICE (gas engine) you are just wasting that energy to spin the ICE.
 

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What RolfS said - light pressure on the brakes does NOT engage the brake pads, just the generator. I live in the foothills of the Rocky Mountains, and on average I use "B" mode about once a month. I'm very glad I have it on long, steep mountain descents, but I never use it in everyday driving.
 

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i guess i'll have to read my 2001 manual again

after testing this theory on a hill i use often
i could swear that the battery recharges quicker
when driving in "B"

i almost always get a full charge when reaching the bottom
but not if coast down in "D" and use the brakes to slow down
 

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I was thinking the same, that the battery is being recharged when you simply let off the gas pedal in D and allow the engine (generator) to do the braking and also the same when you shift into B. I use B quite abit and would be thrilled to hear I am wrong, since that would mean I may be able to bump my mpg average up a tad. I rechecked my '04 manual and it is not clear on this either way as far as I can tell. DanMan, help us out here!

PA P
 

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I believe B applies more regen during drag (the opposite way many of us would like it to operate) so that you don't have to ride the pedal as much. Instead you can control your speed strictly with the accelerator pedal. It may also encourage the ICE to spin to create more drag. But let us recall that ICE spins anyway over 42 MPH.

The classic always applies SOME friction brakes, but the 2004+ doesn't until the speed gets too low to get sufficient regen braking.

Also lets not forget that regen is only 50% efficient, so if you have a choice to brake or not to brake, chose not to; coast more.
 
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