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I've been lookig at used volts for the past week and getting close to purchasing one. 3 years ago I was close to purchasing one also and remember conversations about electric miles vs gas miles when it comes to the total miles on the vehicle. I've tried searching, but did not come accross this topic. What should the breakdown of these be? How do I check on the cars that I test drive? Why do I want higher or lower electric or gas miles? Thank you kindly for your help
 

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Using the Gen1 models as an example. With a ballpark avg of 40mpg, if the lifetime mpg number is 40, that would tell you it was run almost exclusively on gas. If it were 80mpg, then it was run about 50% on gas and 50% electric (one electric mile for every gas mile). If 120mpg, then 40/120= 33% gas. On a Gen2, you'd substitute ~53 for the avg gas mpg.

I don't think there is a consensus as to whether gas or electric miles take more of a toll on the car. Personally, I'd like to see at least a fair share of each, since the owner would have seen (and hopefully taken care of) any problems with either mode. If it's a particularly high mileage vehicle, it would be more understandable if there were a higher number of gas miles -- long commute or lots of long trips.

Do those address your concerns?
 

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The Gen 1 Volt is an exceptional value in a used car. Amazingly good reliability, inexpensive to own, fun to drive, and generally low cost to purchase.

Most people want more EV miles and less gas miles using the logic that the ICE engine wears faster than the electric bits. I hold the idea that you want less miles on the technology you anticipate you will use the most. In reality, I'm not sure it matters than much either way. Overall condition matters more than a few ICE miles.

To get a good estimate of EV miles vs. Gas miles. (credit to Tony Broadway)

Providing the lifetime mpg is below 250:

1. Take the total miles and divide it by the lifetime mpg. This will give you the total number of gallons used.

2. Multiply number of gallons by 37 (which is the epa combined mileage of the Volt). This is miles driven on gas.

3. Subtract the miles driven on gas from the total miles and you will get the electric miles.

Example: My car has total of 7106 miles. Lifetime mpg= 140

1. 7106/140 = 50.76 gallons
2. 50.76 * 37= 1878 miles on gas
3. 7106 - 1878= 5228 electric miles

OnStar reading = 5259 electric miles, so I that gives me an accuracy of 99.4%...pretty darn close.
 

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Keep in mind that a lead foot can impact that formula. When I bought my '13 it had just shy of 93K on the clock with a lifetime mpg of 37.7mpg. According to onstar at the time I had about 69K gas miles, and the remaining 24K or so all electric. Using the above formula indicates I would have seen about 91K of those miles as gas rather than the onstar calculation of 69K which ultimately gives the PO an mpg of about 28 mpg which somewhat jives with the 29 mpg that Voltstats seems to confirm with the mpgCS chart.

Really the whole gas vs. EV concern is that similar to any ICE powered car, lower mileage indicates less potential wear on the engine. Having a higher lifetime MPG seems to indicate less engine usage which should in turn mean that the engine is in newer condition than one that has a low lifetime MPG with high engine use.
 

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Keep in mind that in Extended Range Mode, the Gen 1 Volt uses the gas engine to generate electricity, not to propel the car, so the miles on the odometer were all put there using the electric motor (although under certain conditions the generator, whose shaft is being turned by the engine, is also coupled to the drivetrain, in effect using engine torque to help propel the car). Pamela Fletcher, at the time Chief Engineer, Volt Powertrain, refers to Extended Range Mode driving as "electric-like" driving in her video explaining how the 2011 Volt works (one of the earlier videos on the topic). The Gen 1 Volt’s primary motor is fueled by grid electricity stored in the battery and gas-generated electricity created as needed. Gas Miles are recorded when gas-generated electricity is being created.

Lots of Gas Miles mostly means the car spent more time running on gas-generated electricity. Some owners didn’t bother to recharge. Some regularly drove beyond battery range on their commute. Some may have taken long trips and didn’t stop to recharge. It’s not easy to determine how the Electric/Gas miles ratio came to be... I myself drive my 2012 Volt ~99% ev around town, but once a year or so I take a long vacation drive adding 1000s of gas miles (twice drove from Oregon to Michigan and back).

I suspect the used Gen 1 Volts with the lower Gas Miles were owned by drivers who tried to maximize their electric car driving experience, adopting driving habits that were economically friendly and sometimes pertinent to the genre (such as using heated seats instead of running heat during cold weather or slowing down to make it those final couple of miles home on battery power without starting up the engine), and recognizing that the grid power stored in the battery is used both to fuel the motor and to power the accessories (i.e., the more power you use for air conditioning, the less you have to fuel the motor).
 

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The car may have been registered on VoltStats.
 

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The Gen 1 Volt is an exceptional value in a used car. Amazingly good reliability, inexpensive to own, fun to drive, and generally low cost to purchase.

Most people want more EV miles and less gas miles using the logic that the ICE engine wears faster than the electric bits. I hold the idea that you want less miles on the technology you anticipate you will use the most. In reality, I'm not sure it matters than much either way. Overall condition matters more than a few ICE miles.
More that most of the electric-driven bits that are prone to actual wear (motors, planetary and reducing gears) get used no matter what's powering the thing, and since the battery management is conservative enough that it's good for like 15 years of daily charge cycles, the ICE is the only thing to really preserve via low use. Obviously SOME use is important, but if engineers can figure out how much "some" is, and put it into an automatic maintenance cycle (which they did), then even that's already taken care of.
 
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