58 mpg On First Tank

Discussion in 'Gen 5 Prius Fuel Economy & Prime EV Range' started by VelvetFoot, Nov 15, 2025 at 8:15 AM.

  1. VelvetFoot

    VelvetFoot Member

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    Dealer-filled first tank.
    Went until light came on when it said I could go 30 miles more.
    559 miles, 9.64 gal
    The tank capacity is 11.3 gals?
    I don't think I'm going to test it though. :)
    I kind of babied it, but not super extreme.
    edit: The tank apparently holds 11.4 gals, per the manual:
    upload_2025-11-15_8-18-22.png
    edit 2: Apparently 1.6 gal when the light comes on. At 50 mpg, that'd be...80 miles. If not on an uphill slope assuming the fuel pickup is in the front, lol.
    edit 3: The car computer said 2 mpg higher on the tank.
     
    #1 VelvetFoot, Nov 15, 2025 at 8:15 AM
    Last edited: Nov 15, 2025 at 9:29 AM
  2. sclevine

    sclevine Active Member

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    Congrats! I can't seem to ever get that high, but when I baby it I do get in the mid 50s. But I think the LE's do get a couple higher MPG then the XLE's due to the tire size.

    Yeah the light comes on very early. Just like you'll notice that you'll get about 70-90 miles before the fuel gauge starts to show below Full, I believe similarly you'd get about 70-90 miles once you get below Empty/0 MTG. Not the warning light, but 0 MTG. I'll sometimes let it get to around 0 MTG before I fill and it generally takes 9.5 gallons or so.

    I have my display above steering wheel set to show me MPG for current tank. If it shows me my MTG for the tank is say 55.5, then I know I easily can go 550 miles before refilling, regardless of what the MTG estimates. But I don't really test it below 0 MTG. Again, if I refill at 0 MTG it will take 9.5 gallons (give or take) at that point. Far from the 11.4 capacity. Scanning my Fuelly, I have only had 1 instance where I had a fill up over 10 gallons.

    Also, if your tank is mostly highway driving at high speeds, not only will your MPG be much lower, but the light comes on even earlier than necessary, and at 0 MTG it will take even less - like 9ish gallons.
     
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  3. VelvetFoot

    VelvetFoot Member

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    Our experiences match up pretty well. I did drive a little bit after the light came on. :)
     
  4. bisco

    bisco cookie crumbler

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    great mpg's, congrats!
     
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  5. VelvetFoot

    VelvetFoot Member

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    Thanks!
    I'm not being quite so careful now.

    Should a goal be to keep the EV light lit up as much as possible, or could that lessen the life of the traction battery?
     
  6. bisco

    bisco cookie crumbler

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    it won't hurt the battery, but it actually reduces mpg's, because it takes more energy to replenish the battery than it does to drive hv.
    for best mpg's, the goal should be to stay in hv, or you can research 'pulse and glide' for eco nuts.
    some say, 'just drive it'
     
  7. VelvetFoot

    VelvetFoot Member

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    By that you mean ice and motor are running simultaneously?
     
  8. bisco

    bisco cookie crumbler

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    sometimes. the system takes care of itself. so you won't be pure ev too often, but depending on the input from the go pedal, the required energy and the battery state of charge, the software is providing the best mpg's possible for a computer.
    naturally, there will be times when the battery needs to be bled down. in that case, the software will keep it in ev, or even run the engine to bleed off excess regeneration when going down a mountain.
    basically, it just means on't try to keep it in ev. :)
     
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  9. VelvetFoot

    VelvetFoot Member

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    I find if I back off on the go pedal I can induce "EV mode", ie, the green light come on. I'm wondering if that's a bad thing. I imagine the system knows how to protect itself, but there was a statement in the manual about the life of the traction battery depending on the manner of driving.