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Not complaining. Just pointing it out.

Given that I find the GOM nearly worthless and not paying attention to, why would I care much about the GOM * 1.18 and GOM * (usually) 0.82?
Because you like numbers ? Now answer to me this: why do you think GM chose 1.18 and 0.82 as numbers and not 1.10 and 0.9 ? If you can answer that, I declare you brilliant.
 

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Yes, the same question is for you too. What made GM chose to make the range number (middle in the GOM) greater by 18% than the Min number ?

Here is my opinion : Being that the Min number is a calculated number based on the present driving conditions and climate settings, this number should be then the result of the average efficiency and the battery SOC. Like, if your efficiency after the last reset was 3.4 mi/kWh, the Min number should be around 3.4 x 60 = 204 miles once the battery is full again.

The 1.18 x Min = estimated range number might be the number that empiric tests made by GM have shown to be closer to the reality of the range of the Bolt EV than the Min number.

GM does say that the middle number is a number based on the last couple of days driving conditions, but … being that the middle number is 1.18 x Min in a consistent manner, this might not be the case.

The Max number might be the number obtained by the best efficiency number x SOC (encountered during the last drive since the last average reset).
 

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For me @Voldar is spot on, I don’t want to do a bunch of math in my head while driving down the road and I bet there are a lot more that want to glance at a display and be quite certain that they can get where we are going and not fuss about trying to arrive at the furthest DCFC with the exact Km left according to some math equations by a non GM engineer calculated based on 1 or a few cars.
Seriously, I’m kinda tired of the granularity and rabbit out of a hat expectation’s some ask of the Bolt’s GOM.
It’s a Guess O Meter and IMHO it’s a pretty dam spot on.
 

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For me @Voldar is spot on, I don’t want to do a bunch of math in my head while driving down the road and I bet there are a lot more that want to glance at a display and be quite certain that they can get where we are going and not fuss about trying to arrive at the furthest DCFC with the exact Km left according to some math equations by a non GM engineer calculated based on 1 or a few cars.
Seriously, I’m kinda tired of the granularity and rabbit out of a hat expectation’s some ask of the Bolt’s GOM.
It’s a Guess O Meter and IMHO it’s a pretty dam spot on.
There are people who complain that the MyChevrolet app told them they should be 13% SOC when arrived at the DCFC but instead it was 12% or 15% when they got there. I hear them say "it’s rubbish". I am not gonna comment on this kind of people. It’s enough I can still call them such.
 

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When you'll understand that the Min and Max are not numbers that remain the same, they move up and down based on the current driving conditions and the climate settings... There is nothing about the "future".
I am not sure why are you still complaining about the Min and Max values. You have no longer a Bolt EV, you never used them anyway.

Edit : The "future" is represented by the trend line.
"Current" (however long that is) and past driving is not necessarily indicative of the future. Telling me something isn't helpful if it only applies now and doesn't apply to the future. I need to still keep driving until I reach my destination and my future driving may differ greatly from whatever the black box used to throw up 3 numbers, of which one seems to be 1.18 * guess and the other is usually (almost always?) 0.82 * guess.

I got turned off by GOMs long ago. I remember with my Leaf I started out at 80 miles on the GOM. After driving 8 miles, it went up to 88 miles. Did I gain energy in my battery? NO!!!

Of course, if I go on the highway it ticks down by more than 1 mile for each mile driving. If I drive up highway 17 (steep hill), it'll drop by 40 miles after traveling 10 miles. Why bother? Once I crest the hill and start going downhill, the GOM mostly remains unchanged.

Of course, '13+ Leaf got a 1% increment SoC display whereas '11 and '12 didn't have one and there were LOTS of complaints.

Bolt's GOM values are all over the place too and go up/down based upon just turning the heater or AC on/off (like Leaf) and then you get auto-defog doing things behind your back. Even if you disable it, it for some reason turns itself back on for no rhyme or reason.

When I drove '13 Leaf to work and I was going in w/low juice, what mattered for me was the %. I wouldn't go to work with under 25% on a dry day. I know it takes normally 12 to 18% to get there on a dry day and on the lower side if there's a traffic jam. I know if I leave with 25%, I'll usually hit the 1st low battery warning on my way there but that's no problem. I have free L2 charging at work.

My utility is Pacific Gouge & Extort. If I need to add some/a bit of juice at home, then I prefer to add as little as possible + enough buffer to make it to work and no more.

What would I need on the GOM? Who knows? Who cares? If I drove really efficiently on the way home, the GOM will be high. If I drove inefficiently home and/or it was cold and rainy, the GOM will be low.

IIRC, if I hit the 2nd LBW (aka VLBW), the GOM turns to --- miles! Thanks a lot!

If it's a cold, rainy day, I leave with at least 30% SoC.

If I return home from work (about half highway and half city and under 12 miles total) on Friday with the Bolt ending at whatever GOM, how does this help if I go on a trip to Sacramento that is ~130 miles away, almost all highway? As we all know, the GOM can read high in the spring and very low in winter... But the weather on Friday could be very different from Saturday.

(I no longer have the Leaf, but if you look at page 2 of https://www.pge.com/tariffs/assets/pdf/tariffbook/ELEC_SCHEDS_E-TOU-C.pdf, if I were to charge an EV at home, that'd push me into tier 2 and my marginal cost per kWh would be either 37.4 or 42.5 cents per kWh off-peak. There is EV2-A, see page 2 of https://www.pge.com/tariffs/assets/pdf/tariffbook/ELEC_SCHEDS_EV2 (Sch).pdf where it's 24.7 cents/kWh off peak but kill you with 41.5 to 56 cents per kWh rest of day.)
 

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You have the SOC % in units of 5%.
You have the efficiency (the average number) in the middle of the screen.
You do the math at every second of your trip you like and be done with it.
Only idiots dont understand approximation, I am sure you aren’t one.

So, if your average is 3.7 mi/kWh, your SOC shows on the gauge 75% mark, multiply 3.7 x 70% x 60 kWh and be done with it. You have your range left at that moment.

Now, 10 mins later it starts raining, with a big head-wind. Your efficiency dropped to 3.1 mi/kWh, your gauge SOC shows 70%. You do the math again (3.1 x 65% x 60) and you’ll see what you calculated first time no longer is accurate.

Why I chose the 65 instead of 70 or 70 instead of 75 ? Because the SOC gauge stays green all the way from 70 to 74.9 or 65 to 69.9. So, to be safe, use the lower number. I doubt anyone would calculate the range using for exemple 73%. Only if he is a computational prodigy or … anal about the values he likes to deal with.

The GOM of ANY EV doesn’t predict the future. It only predicts what you may get IF YOUR DRIVING CONDITIONS ARE THE SAME AS THE PRESENT ONES. The numbers you see in the DIC of the Bolt EV are just that. GM did a great job with the GOM. It answers the need of people like me and people like you, as long the people understood it. If not, you can ***** about GOM until the end of time, I am no longer interested.

There is a whole thread about the GOM in this forum. 400+ messages on it, I am tired to repeat.
 

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I feel the need to step in, this forum community has a mix of experienced owners who have spent considerable time and effort wrapping their heads around the GOM question. We also have a lot of new owners, particularly with price drops, we can expect a lot of new members to turn to this site for answers.

To new owners: As you can see, it frustrates a lot of seasoned owners to rehash topics that have been discussed at great length many times before. This is why we have sticky threads in the New Owner Intro section on the topic, and why we direct new owners to spend time in these in the new Welcome letter we started sending out to new members a week or so ago. So, please, use the resources we provide.

To existing owners: We all went through the frustrations of mastering the GOM. With all the new owners showing up on the site, it is inevitable the topic returns regularly. My suggestion is to bookmark the best explanations and direct new posts to these with a link. If you need help with bookmarking, check out the FAQ section of the forum.

We are also gathering some input on topics to create content that would be helpful for new members. If you have ideas, let the staff know in Private Messages.
 

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I’m assuming cwerdna also does not use GPS navigation, because the app says you’ll get to your destination in X minutes, but you might change your speed, or there might be an accident, so it is COMPLETELY USELESS!
 
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