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I'm sure i'm going to regret asking, but when do people use L on the gearing? I tend to drive in normal mode and D and not worry too much about sport or Low.. so I'm wondering how others use it and what the benefits are?
 

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(L)ow provides much more re-gen to the battery pack, so I use it when I am driving in stop and go city traffic. Your brake pads will also last much longer, because you are not wasting that energy as heat.

Sport mode just changes the feel of the accelerator pedal. There is more low end power, but you sacrifice CD mileage. But sometimes it is worth it!

You have to play with the settings to see what you like!

It is one of the real design advantages of the Volt, that you can change the parameters to suit your own driving style.

C-5277
 

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Low remaps the accelerator petal (gas) and decelerator petal (brake), so that even with your foot partially down on the accelerator, if the car is moving, it will regenerative power capture, and the decelerator petal has less "regen" before it hits to friction breaks.

You can get equal regen using D and the decelerator petal.. just takes a different feathering of the petals.
I find D makes its easier for me to "coast" (retain momentum) but L makes it easer to decelerate and recover power when I want to stop. I use it more like an engine brake when getting off the highway and use L most of the time, on street/stop/go driving. I'm getting more comfortable using L, but I find that if I'm not paying attention I pull off the accelerator strongly and "regen" too much. I used D going to work (down hill) and L coming back (uphill). But I do like the "down shift" into L, its a bit more sports car like.

I agree with Jim.. experiment and see what works for you. Its not that one setting is more efficient than the other, its about how you can use them to get your own efficiency while improving your fun factor.
 

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Besides stop-and-go traffic, I use L whenever I want to slow down somewhat quickly (and finish with the brake pedal as necessary). I also use L when going down a steep hill where "coasting" in D would allow the car speed up and exceed the speed limit. So, I shift in and out of L frequently.
 

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I always use L, and almost always Sport. The D mode just makes this EV more like an ICE vehicle in feel. If you use Sport, it just means that more of the car torque is available with less lag. If they didn't provide some smoothing of the available torque, the car would be unmanageably brisk off the line.

Give the combo a couple hours of trial an you'll never want to go back to the more boring settings.
 

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I pretty much use Normal and Low all the time. I get more mileage using L than when I use D. I also prefer the more aggressive slowing it provides in a given distance vs. D. YMMV.
 

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The overriding reason why I like the L mode is single-pedal driving. Even when going down a steep hill, I can control the speed to be at speed limit with my foot finely modulating the Go pedal. It took a few weeks for me to get the adjustments right. In my ICE car, I have to use the brake to stay within limits. On the freeway during widely varying speeds at peak hour, I find that I am able to better maintain position within traffic in L-mode. In D-mode, I have to switch back and forth between the pedals and I find that this is not as smooth and seamless as just using foot position on one pedal.

Not sure if anyone else has noticed, but the Volt does not have too much lift room when switching pedals. I end up hitting the roof or sidewall with my foot when moving between pedals. Another reason why I like the L-mode.

-Venky
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2011 Viridian Joule, Leased 7/5/11, Odometer: 1500 (Electric: 1400)
 

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(L)ow provides much more re-gen to the battery pack, so I use it when I am driving in stop and go city traffic. Your brake pads will also last much longer, because you are not wasting that energy as heat.
I don't think these statements are true. It's just remapping the pedals as tboult stated.
Think of two scales:
1. friction braking ---- strong regen --- light regen --- coasting --- acceleration
2. brake pedal fully depressed --- brake lightly depressed --- both pedals released -- light accelerator -- heavy accelerator

Shifting to low just shifts the second scale left with respect to the first one. You still get the same regen in "D", it's just you have to press the brake pedal a bit more. The regen is still saving your brake pads, until you press hard enough to actually engage them. Just because you are using the pedal doesn't mean you are using the pads. L just gives you more of an assurance that you aren't engaging the pads since you aren't on the brake pedal, but that's basically a mental thing. Maybe they should make the green ball change color or something more definitive when the pads are engaged.

I'm pretty sure that the same efficiency can be obtained in both modes, at least any difference is way smaller compared to things like average speed, and climate control use. Less difference than I can measure anyway from inability to exactly match conditions from drive to drive. So it boils down to personal preference. For max efficiency, in "D", you just have to concentrate on braking early & gently, probably earlier than you are used to in a std ICE car (along with other std high MPG practices). In a std ICE, there's no particular advantage in braking earlier, since you are converting momentum into heat in any case. But with regenerative brakes you have incentive to brake early so you can do it gently, keeping the green ball mostly on the center target, not diving to the bottom, slowing down using the regen instead of the pads so some portion of the momentum can be recaptured.

In "L", you have to fight any tendency to yo-yo your speed too much, which is inefficient. It gives you a bit finer control of the speed I think (accelerator is easier to finely control than the brake pedal), but over-controlling it is worse than maintaining momentum for efficiency.

After trying exclusive "L" for a couple weeks, I've gone back to "D" mostly on the expressways for most of my miles, but switch to "L" in stop-and-go conditions and for controlling speed on downhills. Your preference may vary.
 

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I always use L, and almost always Sport. The D mode just makes this EV more like an ICE vehicle in feel.
Exactly.

I started out playing with L shortly after getting the Volt, and now use it exclusively. A few days ago, I needed to drive a few miles in 'D', and it felt like like an ICE vehicle.
 

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L just gives you more of an assurance that you aren't engaging the pads since you aren't on the brake pedal, but that's basically a mental thing. Maybe they should make the green ball change color or something more definitive when the pads are engaged.
That's the catch. We know that when stepping on the brakes, the regen is used, but it maxes out at some point and the friction brakes are used. Presumably, the 'L' mode maximizes the regen to the point just before which the friction brakes would kick in. In 'D' mode, there isn't any way to determine whether regen or friction brakes are being used. So either you'll err on the safe side (and only use regen, but not as much as you could), or end up using the friction brakes more than needed.

Of course, my argument depends on the fact that 'L' maximizes regen, and I don't think we've seen anything definitive about that.
 

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I like using low all the time now too. I didn't think I would but the one pedal driving is really neat and I know I am maximizing my regen when coming to a stop, only using the brakes to stop that final 10kph. You can also feather the accelerator an get the good coasting regen too with out the aggressive regen braking in low if you want to coast. It also works well with cruise control. I live in rolling hill country and low really lets CC keep the speed in check.
 

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(L)ow provides much more re-gen to the battery pack, so I use it when I am driving in stop and go city traffic. Your brake pads will also last much longer, because you are not wasting that energy as heat.
I would dispute this statement. Why does the brake pedal say "Voltec" and not the shift lever? The myth that you don't get good regen in Drive is not based in good engineering data.

I just drove 860 miles yesterday going through the mountains, and kept it in D the whole time, including going down then the mountain passes. Usually the cruise kept the speed from overrunning, and the gradual braking certainly provides regen. Only once in the trip did I have to brake hard (as I would want it), and that was when someone cut in front of me. There is also the little "detail" about the brake lights and those behind you. One Volt owner who always drives in low told me how a driver pulled beside him and in a perturbed way, told him his brake lights weren't working. The legalistic answer "but I never touched the brake" doesn't show consideration for the person behind you (who may be distracted on the cell phone, etc.) and the surprise when you slow down without the usual visual cues. To me, the car feels much more normal and less distracting in D. I like the car to much to go begging for a rear end collision.
 

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One Volt owner who always drives in low told me how a driver pulled beside him and in a perturbed way, told him his brake lights weren't working. The legalistic answer "but I never touched the brake" doesn't show consideration for the person behind you (who may be distracted on the cell phone, etc.) and the surprise when you slow down without the usual visual cues. To me, the car feels much more normal and less distracting in D. I like the car to much to go begging for a rear end collision.
And the guy on the cell phone being distracted is showing you consideration? Sorry one of my pet peeves!
 

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And the guy on the cell phone being distracted is showing you consideration? Sorry one of my pet peeves!
I could care less about consideration, respect, etc. from other drivers - I just drive considerately and defensively myself (caution, courtesy and common sense), as if anyone out there could be unexpectedly drunk, stoned, or otherwise crazy.

The trip through the mountains made me realize that of all vehicles, the Volt is the **least** likely to need to be put in low. Had I been taking the trip in my Yukon XL, I would be wearing my pads if I didn't downshift, but the Volt is putting nearly all of that energy back into the battery. If you don't believe me, watch the animated display on the center display.
 

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There is also the little "detail" about the brake lights and those behind you. One Volt owner who always drives in low told me how a driver pulled beside him and in a perturbed way, told him his brake lights weren't working. The legalistic answer "but I never touched the brake" doesn't show consideration for the person behind you (who may be distracted on the cell phone, etc.) and the surprise when you slow down without the usual visual cues.
Yes, I see this as a very realistic concern as I coast frequently even in my ICE vehicle. I think a simple red/orange/green indicator to replace the now mandatory third brake light would be intuitive. Green=accelerating or maintaining speed, Orange=coasting or light regen, and Red=brake pedal stopping or heavy regen (traditional brake lights would also activate as usual).
 

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I use L all of the time (city and highway), and Normal most of time (except the occassional use of Sport to zoom away from a stoplight). I guess I'm still unclear whether Sport mode actually gives a faster acceleration, or just a different pedal feel.
 

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When I had a stick-shift car, I coasted all the time in neutral. No brake lights either when I was slowing down. This seems similar to driving in L.
 

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At the Volt homecoming a GM engineer gave me this tidbit. In (L) it's a lot easier to max the regen and know when the friction brakes kick in. If you step on the brakes a little bit so that the ball moves down a little that's max regen, as the rotating leaf fades out that's the friction brakes coming into play. The same thing happens in (D) but when the ball is a lot lower, hence it's a lot harder to ride that edge of max regen and no friction brake. I pushed him to update the ball to actually show when the friction brakes kick in. I don't think they'll do that.

He also gave me this tidbit that he says he's not seem on this site. Yes, every GM person I talked to monitors this site. The forward creep is slowing in (L) than (D) - perfect for parking lots or parking in the garage. Also, you'll get more wheel slip in (L) than (D) with that thought that if you're stuck in the snow you need less traction control.
 

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I could care less about consideration, respect, etc. from other drivers - I just drive considerately and defensively myself (caution, courtesy and common sense), as if anyone out there could be unexpectedly drunk, stoned, or otherwise crazy.

The trip through the mountains made me realize that of all vehicles, the Volt is the **least** likely to need to be put in low. Had I been taking the trip in my Yukon XL, I would be wearing my pads if I didn't downshift, but the Volt is putting nearly all of that energy back into the battery. If you don't believe me, watch the animated display on the center display.
Bob,
If you were in your Yukon and downshifted to save your brakes your brake lites would not be on just like L in the Volt so if you are concerened about brake lites why downshift. Most manual cars downshift and have no brake lites so not diff than L.
I almost always drive in L so I get the one pedal driving and it is very easy to learn to feather the go pedal to get max regen or coasting. In light traffic on the highway D might be OK.

Roy #272 --4100 miles and 2.3 gal of gas
 

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It was once stated on the forum, by a GM person, that the transition from regen braking to friction braking in D mode occurs when the rotating leaves disappear from the efficiency ball. I have no way of confirming this......
 
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