# Dashboard "Miles Till Empty" - how accurate? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [August 4, 2015, 5:09pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985 "2015-08-04T17:09:51Z")\ **Posts on this page:** 8\ **Page:** 9
**Author:** ![AnaMen](https://avatars.discourse-cdn.com/v4/letter/a/dfb087/32.png) [@AnaMen](https://boards.straightdope.com/u/AnaMen)\ **Post date:** [August 11, 2015, 2:30pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985/161 "2015-08-11T14:30:06Z")
> [@enipla](#): > > If you are stuck in traffic or at a traffic light, it won’t matter one bit how ‘sensitive’ you are. If there is no where to pull over very quickly and safely, it won’t matter how ‘sensitive’ you are. That’s not how it works in any car I’ve owned. Feel free to remain unconvinced. ---
**Author:** ![AnaMen](https://avatars.discourse-cdn.com/v4/letter/a/dfb087/32.png) [@AnaMen](https://boards.straightdope.com/u/AnaMen)\ **Post date:** [August 11, 2015, 2:35pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985/162 "2015-08-11T14:35:41Z")
> [@Thudlow\_Boink](#): > > If you make it a practice always to have at least (say) a gallon in your tank, doesn’t this have the exact same effect as having a reserve tank? I am baffled as to why someone would advocate the latter but spurn the former. No, it doesn’t. I’m talking about a reserve tank that one manually switches over to when necessary. It needn’t actually be a separate tank, but can be a lower access point in the same tank. The key to “reserving” the fuel is the manual switch-over. ---
**Author:** ![SmellMyWort](https://avatars.discourse-cdn.com/v4/letter/s/ea5d25/32.png) [@SmellMyWort](https://boards.straightdope.com/u/SmellMyWort)\ **Post date:** [August 11, 2015, 2:47pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985/163 "2015-08-11T14:47:12Z")
> [@Machine\_Elf](#): > > It might have been more helpful to know how much time was spent doing everything _but_ pumping gas. You spent 4:03 from turning in to turning out, but how much of that was spent pumping gas, and how much was overhead? > > It’s weird to me that some people here think anything less than half a tank - enough fuel for most cars to travel a couple hundred miles - is “far enough to risk running empty.” Yeah, I realized that too late :smack: but figured I’d at least mention it. And just to be clear, I only mentioned half a tank since that’s what **AnaMen** was basing her comparison on. I think it’s far more common for people to fill up at a quarter tank or at some point after their gas light goes on. I think my typical fill-up is usually over 15 gallons, but this particular time I knew I was driving out of town the next day and wanted to start with a fresh tank. I was a little surprised it only took 4 minutes. ---
**Author:** ![slash2k](https://avatars.discourse-cdn.com/v4/letter/s/439d5e/32.png) [@slash2k](https://boards.straightdope.com/u/slash2k)\ **Post date:** [August 11, 2015, 2:52pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985/164 "2015-08-11T14:52:34Z")
> [@AnaMen](#): > > No, it doesn’t. I’m talking about a reserve tank that one manually switches over to when necessary. It needn’t actually be a separate tank, but can be a lower access point in the same tank. The key to “reserving” the fuel is the manual switch-over. Why do you need a manual switchover? Can’t you just do it mentally? That’s what the rest of us do: when we get into the last X gallons (where X depends upon vehicle, driving habits, location, etc.), we’re into the reserve fuel and need to get more. We’re not so technologically dependent that we have to have a switch to figure that out. ---
**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\ **Post date:** [August 11, 2015, 3:00pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985/165 "2015-08-11T15:00:01Z")
> [@AnaMen](#): > > That’s not how it works in any car I’ve owned. Feel free to remain unconvinced. You’ve done absolutely nothing to convince any of us, so yes, I will remain unconvinced. ---
**Author:** ![AnaMen](https://avatars.discourse-cdn.com/v4/letter/a/dfb087/32.png) [@AnaMen](https://boards.straightdope.com/u/AnaMen)\ **Post date:** [August 11, 2015, 4:02pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985/166 "2015-08-11T16:02:03Z")
> [@slash2k](#): > > Why do you need a manual switchover? Can’t you just do it mentally? That’s what the rest of us do: when we get into the last X gallons (where X depends upon vehicle, driving habits, location, etc.), we’re into the reserve fuel and need to get more. We’re not so technologically dependent that we have to have a switch to figure that out. I don’t need it-- if I did, I’d have it, obviously. I just think it would be a nice feature. I also have a mental “reserve” amount, but it depends on the conditions because I like to cut it very close to minimize my stops. With an actual reserve, I could cut it even closer, which would be cool. ---
**Author:** ![SmellMyWort](https://avatars.discourse-cdn.com/v4/letter/s/ea5d25/32.png) [@SmellMyWort](https://boards.straightdope.com/u/SmellMyWort)\ **Post date:** [August 11, 2015, 4:02pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985/167 "2015-08-11T16:02:11Z")
> [@AnaMen](#): > > Last year I drove about 36,000 miles. My car gets about 36 mpg and has a tank that holds about 10 gallons of gas. Therefore, let’s say I get 360 miles per tank and must therefore have stopped about 100 times to fill up. Let’s use your time estimate and say each time took 5 minutes (if only that were true!). That means I spent 500 minutes getting gas last year (maybe if I always drove alone this could be true, but I don’t). > > Of course I pay at the pump, for maximum efficiency. The time I spend turning into the station (possibly waiting for a break in traffic), driving to the pump, getting out of the car, getting my credit card out of my wallet, poking it into the machine, entering my zip code, removing my gas cap, waiting for approval, choosing my octane, waiting for the pump to start, hanging the pump handle back up, putting my gas cap back on, waiting for my receipt, getting back in the car, starting the car, and driving out of the station (possibly again having to wait for a break in traffic), will be the same, regardless of how much gas I get. This takes a non-zero amount of time. Let’s call it X. > > So if you drove the same amount, got the same mileage I did, and have the same size tank, but stopped for gas twice as often, you stopped 200 times. If filling up takes 5 minutes, your stops took X + [(5 - X)/2] to fill half of your tank instead of the whole thing. Multiply that by your 200 stops and you get 500 + 100X as the total number of minutes you stopped, versus my 500 minutes. So if that stuff I listed and called “X” is under 1 minute 12 seconds, I guess you are right, and 2 or more hours were not saved. But it isn’t, and not only did I save hours, but I spent them doing something better than the horrid series of mini-waiting-intervals involved in getting gas. I hate waiting, so getting gas extra times is not for me. Obviously there are many different factors that come into play. That’s a small tank and a lot of miles, well over twice the national average. You could have mentioned that earlier so other posters would be more in tune with your point of view. I doubt anyone wants to get gas 4 times a week if they don’t have to. For me, the difference between coasting in on fumes or getting gas at some point after the light goes on is only 5-6 stops per year, so maybe 10-15 minutes wasted every year. But not wasted because that tiny amount of time is worth it to me to minimize my chance of running out of gas, which would be more than a minor inconvenience. And I use it to clean my windows:cool: ---
**Author:** ![AnaMen](https://avatars.discourse-cdn.com/v4/letter/a/dfb087/32.png) [@AnaMen](https://boards.straightdope.com/u/AnaMen)\ **Post date:** [August 11, 2015, 4:19pm UTC](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985/168 "2015-08-11T16:19:48Z")
> [@SmellMyWort](#): > > Obviously there are many different factors that come into play. That’s a small tank and a lot of miles, well over twice the national average. You could have mentioned that earlier so other posters would be more in tune with your point of view. I doubt anyone wants to get gas 4 times a week if they don’t have to. > > For me, the difference between coasting in on fumes or getting gas at some point after the light goes on is only 5-6 stops per year, so maybe 10-15 minutes wasted every year. But not wasted because that tiny amount of time is worth it to me to minimize my chance of running out of gas, which would be more than a minor inconvenience. And I use it to clean my windows:cool: Ha, they’d just claim that’s more times I’m rending the fabric of society with my callous disregard for the well-being of others. I’m not trying to convince anyone to get gas less often. Stop for gas whenever you like, just like I do. It sounds like you’ve worked out a system that you are satisfied with, just like I have, so there’s no need for either of us to switch. [Previous page](https://boards.straightdope.com/t/dashboard-miles-till-empty-how-accurate/726985.md?page=8)