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When do you fill up your gas tank?

Discussion in 'Gen 3 Prius Fuel Economy' started by mediahound, Sep 17, 2013.

  1. mediahound

    mediahound Active Member

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    Gas is heavy so you get better mileage as your gas tank gets more empty, which should bring up your MPG average.

    So when do you fill up typically? Is it best to wait until its almost empty?
     
  2. bisco

    bisco cookie crumbler

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    it's not heavy enough to make a noticeable difference. when the last pip blinks if i'm in familiar territory and at two pips if not.
     
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  3. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    Do you know what is really heavy? A gas can with at least 3 gallons of gas so you can start your car again. I start looking when the MTE is under 50.
     
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  4. Mike Rosenzweig

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    Since I live in an area that is subject to possible natural disasters and weather woes, I always fill up with 3 pips remaining. To me, its from old habit of filling up at quarter tank on my previous cars.

    SAMSUNG-SGH-I317 ? 2
     
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  5. mediahound

    mediahound Active Member

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    Ya, I guess I'll just fill up when it's convenient.
     
  6. ursle

    ursle Gas miser

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    When I need gas, and I put in oil and air when needed.
     
  7. Wayward

    Wayward Member

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    I typically wait until I am at 0 DTE if not 20 miles past.
    Of course having only a 10 mile commute makes it pretty easy to know when I will get to the next gas station.
    Funny thing is my wife's car I fill up at 1/4 tank every time but the Prius I want the 450-500+ miles per tank.
    I hate that I have to fill-up my wife's tank after like 260 miles and it costs me $50 and I can go twice as far for $35.
     
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  8. dhanson865

    dhanson865 Expert and Devil's advocate

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    No DTE on my Gen II so:

    If the weather is nice I fill up when I've gone 500 miles on a tank (usually hit that with 1 pip left), if the weather isn't nice (winter, raining, long trip planned, anything unusual) I fill up with 2 pips left or something like 400 miles used on the old tank.
     
  9. Ray-o-Vac

    Ray-o-Vac Junior Member

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    I'll start looking when the last pip is blinking and I am past 500 miles on the tank in familiar territory.
    2 pips regardless of the mileage when I am in unfamiliar territory.
    Being as I am still relatively new to the Prius (4 months) I may have to rethink this when the cooler weather sets in.
     
  10. El Dobro

    El Dobro A Member

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    I start looking for gas around 2 pips.
     
  11. fuzzy1

    fuzzy1 Senior Member

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    The mpg loss from fuel weight isn't very much. I'd prefer to lose that weight in unnecessary cargo, especially that spare tire stored at just about belt level. There is more money to be saved by strategically planning refills based on price and route convenience.

    When to fill up? Near home with ordinary short trips, when fuel prices are stable, I typically refill at 2 or 3 bars. Longer trips away from home, I shop by best price along the route, filling anytime from 6 bars to well past DTE = 0. Unfamiliar routes require more margin, be certain the next couple supposedly open fuels don't require dipping into the known comfortable margin. Adverse weather (snow, avalanche prone mountain routes) requires a couple extra bars of margin.

    To paraphrase a guideline Jimbo has posted to other threads (particularly in GenII, more prone than GenIII to prematurely running dry):
    * With the mother-in-law in the car, refill at three bars. She will never stop reminding everybody that you stranded her;
    * With the spouse in the car, refill at two bars. She will never forget that you stranded her;
    * When driving alone, refill at one bar. No one else needs to know that you ran out of gas.

    Because I like to travel in areas such as pictured below, planning ahead to the next fuel is essential, especially in older cars with much shorter fuel range. By the time a low fuel warning lights up, it might be too late.
    [​IMG] [​IMG]
     
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  12. SuperGLS

    SuperGLS Member

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    I can't envision a situation where I would fill up before it was flashing at me. First tank I went 20+ miles past DTE=0 and still had two gallons left.
     
  13. fuzzy1

    fuzzy1 Senior Member

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    How about Hiway 30 from Snowville Utah towards Wells Nevada? That has one of the "Next Service 100+ miles" signs that I didn't snap a picture of. Drive at rural speeds, or add some rain or snow and a headwind, and you may not make it.

    My old V8 Ford, starting with a needle on 1/2 tank, probably wouldn't make it even on a dry windless road while obeying the then-national 55 mph speed limit.
     
  14. SuperGLS

    SuperGLS Member

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    Right. But I'll never be driving there. I meant for me personally, I don't think I'm likely to be in that situation.
     
  15. bwilson4web

    bwilson4web BMW i3 and Model 3

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    God is laughing and Mother Nature has made a new entry in her list:
    In April 2011, a string of tornadoes ripped up the TVA transmission lines in North Alabama. The nearest power needed to operate gas stations and grocery stores was about 80 miles South of our home. As power returned to the region, it eventually reached Decatur, about 35 miles away.

    Bob Wilson
     
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  16. SuperGLS

    SuperGLS Member

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    Hah. I'll take my chances. If a tornado comes to claim me I'll have a bit more to worry about than not having a full tank of gas!
     
  17. ewxlt66

    ewxlt66 Active Member

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    Usually at one pip or at the blink. Ain't nobody got time for that.
     
  18. El Dobro

    El Dobro A Member

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    When there's any notification of a storm approaching, I fill the tank and charge the battery all the way up. That came in real handy when Sandy hit and I used the car as a generator.
     
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  19. GardenWeasel

    GardenWeasel Member

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    I usually need 9 to 9.5 gallon on a fill...and last pip is flashing.