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Hello,
I've always driven the car in "Low" thinking that I'm getting more eMPG because it's charging the battery more. I drove the car in "Drive" the other day and started thinking I have less rolling resistance (vs harder deceleration braking- charging the battery). Maybe I could go further if the car "rolled" more (if that makes any sense). I'm talking normal freeway speeds and backing off the pedal from time to time as cars pull in front or going down a small hill and having to back off the pedal.


Do you guys know the proper technic to use?
DAVE
 

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Coasting will always be more efficient than regen as there is always a loss of energy in the transfer process (entropy), and regen is more efficient than using friction brakes for the same reason.

In general, on long stretches of freeway driving, I personally just leave it in D to maximize coasting.

When I suspect that I'm going to be in a lot of stop and go, I switch to L to minimize the use of the brake pedal and having to move my foot back and forth.
 

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The best technique is to try to maintain your speed ("coasting", as Cardyin said). Every time you slow down, even if you're using regen to do it, you loose some energy. Regen helps to recover some of that energy, but it's not 100% efficient so you won't recoup as much as you lost slowing down.

If you find it easier to coast (i.e., avoid using any power or any regen) in "D" mode then that's the better mode for you. If you find it easier in "L" mode, than go for it.

You can also use the cruise control, but if you're not driving on a perfectly flat road it may be better to control the throttle manually. In gently rolling hills cruise control will waste energy trying to slow you down on the downhill portions, whereas good manual driving technique can use the gravity assist on those downhill portions to build up some momentum to carry you over the uphill portions.
 

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Hello,
I've always driven the car in "Low" thinking that I'm getting more eMPG because it's charging the battery more. I drove the car in "Drive" the other day and started thinking I have less rolling resistance (vs harder deceleration braking- charging the battery). Maybe I could go further if the car "rolled" more (if that makes any sense). I'm talking normal freeway speeds and backing off the pedal from time to time as cars pull in front or going down a small hill and having to back off the pedal.


Do you guys know the proper technic to use?
DAVE
I know it sounds like a bit unsafe but driving in the highway the best way to extend range is to draft behind a semi. They hate it but if you keep the right distance and keep car in low don't use cruise and you will notice about a 10-20% boost in range or efficiency is what I find.
 

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....Why would you try to draft behind a semi? I mean.. even if it's possible that you'll get a bit more range out of it, there are quite a few cons that come about from that as well that just make it very not worth it in my opinion.
 

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^ not to mention the beating your front end paint job takes being only several feet behind a truck!
 

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If you're not tailgating then why would they care if you're following them?
I've been wondering about that too. I've often heard that truck drivers hate drafters, but I can't for the life of me figure out why they would care. I suppose if someone gets too close and hits you, there is paperwork to fill out, but I would think that would be fully offset by the entertainment value of some fool messing up his fancy electric car while your truck is completely unscathed. A serious accident would be bad, of course, but it seems unlikely to result from drafting, unless of course you're a Tesla autopilot user.
 

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Is the suggested following distance between vehicles still one car length for every 10mph of speed, or has something changed over the last few years?
Drafting requires you to be within several feet of the truck at highway speeds IIRC.... isn't that considered tailgating then?
 

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Is the suggested following distance between vehicles still one car length for every 10mph of speed, or has something changed over the last few years?
Here's what treehugger.com says about it:

" In scaled wind-tunnel tests, driving 100 feet behind a semi at 55 mph will reduce drag on your car by 40%. The drag reduction increases as you approach the bumper of the truck until you get a 93% drag reduction at a distance of 2 feet.

* In road tests, the testers achieved an almost 20% improvement in gas mileage at a distance of 100 feet (at 55 mph) and a 45% improvement at 10 feet."

100 feet is more than 7 Bolt-lengths, and generally would be more than one car length per 10mph at truck speed. This certainly would not be considered tailgating by most drivers in California! I don't draft semis - partly because I have never been short on range in the Bolt, and partly because I just don't drive that way. But I still don't get why truck drivers would care. Unless you're going for that 45% fuel efficiency improvement and following at 10 feet...
 

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Thanks Phil....

I imagine that the truckers aren't concerned with 100ft drafters...
Can they even see a car at 10' behind the trailer?
 

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"In road tests, the testers achieved an almost 20% improvement in gas mileage at a distance of 100 feet (at 55 mph) and a 45% improvement at 10 feet."
I follow semitrailers at the same distance I follow everyone else - 2 seconds behind. At 55mph that works out to about 160 feet. So I imagine I might expect a 5 to 10 percent improvement.

But I don't follow semitrailers because I expect to get better gas mileage through drafting. I follow them so that I can get better gas mileage by driving slower. When you're behind a slow truck the impatient drivers blame the truck instead of you. It also means they only have to change lanes once to pass both of us.
 

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But I don't follow semitrailers because I expect to get better gas mileage through drafting. I follow them so that I can get better gas mileage by driving slower. When you're behind a slow truck the impatient drivers blame the truck instead of you. It also means they only have to change lanes once to pass both of us.
I also like that if there's a big accident ahead, they'll plow a hole through it and give me a few extra seconds to brake/avoid the maelstrom!
 

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This seems like the appropriate thread for my question. So in the two test drives I've taken, I've not been able to change from "D" to "L" and back to "D" without first stopping the vehicle and going into Park or Neutral. The sales people were no help. I downloaded the owners manual, but have yet to find the answer. The section on shifting is not clear on the subject matter. It seems to me one should be able to shift from "D" to "L" (low) without stopping.

Any hints?

Thanks
 

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If you're in D... just pull the shifter back one time... it will put you in L.
If you're in L... just pull the shifter back one time... it will put you back in D.

Don't press the side button on the shifter.
 

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If you're in D... just pull the shifter back one time... it will put you in L.
If you're in L... just pull the shifter back one time... it will put you back in D.

Don't press the side button on the shifter.
Yes, it's counterintuitive, but after the car is in D, just pull the lever towards the back of the car to get it into L, then again to return it back to D. The shifter basically becomes a toggle switch.
 

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Yes, it's counterintuitive, but after the car is in D, just pull the lever towards the back of the car to get it into L, then again to return it back to D. The shifter basically becomes a toggle switch.
The reason for this design is that if you had to push the lever forward to go from "L" to "D" then people who forgot they were in "D" already would end up in neutral, which sets them up for an accident if they suddenly need power.
 

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Is the suggested following distance between vehicles still one car length for every 10mph of speed, or has something changed over the last few years?
Drafting requires you to be within several feet of the truck at highway speeds IIRC.... isn't that considered tailgating then?
The recommended following distance is now based on time and not car lengths. Generally 2 to 3 seconds. Basically you start counting when the car in front of you passes a fixed object, like a road sign. If you get to 2 seconds before you pass the same mark, you are fine. If you only get to 1-Mississippi, or part of 2-Mississipi, then you need to increase your following distance.
 

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^ thanks for that...

Around here it should be easy to mark the time between when the car ahead of you hits the gigantic pothole and when you hit that same gigantic pothole >:)

1-Mississippi, 2-Mississipi...BANG!!
 

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Just use the collision avoidance warning. I have mine set @ 2.5 seconds and when it goes orange,
I know, I'm too close for comfort. No need to count and distract yourself from the task at hand :nerd:
 
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