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MPG 4MPG lower after Software upgrade/Recall

Discussion in 'Gen 3 Prius Main Forum' started by jl2013Prius, Jan 14, 2019.

  1. ASRDogman

    ASRDogman Senior Member

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    The hardest part of changing the fluid in the trans is getting the Prius high enough and level!
    The rest is easy. I too use the hose from the top. I put a screw driver on top of the hose going into the
    filler so air can escape and it fills quicker.
     
    Mendel Leisk likes this.
  2. FF0000Five

    FF0000Five Junior Member

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    What do people normally get with your Priui? I have a 2016. In the winter with the snow tires on, I generally get around 50MPG. In the summer with the stock tires, I would get 65 MPG with mixed driving. I blew out a tire last fall (thanks New England pot holes) and ended up getting Firestone Serenity Plus tires. They were rated very highly across the board. While my snows were on, I had the software upgrade done. My mileage felt a little low all winter, but it was a cold winter too. However, now that I have the Firestones on the car, I haven't done better than 55MPG. That's a HUGE drop and I have a hard time believing it's all due to different tires.
     
  3. BZzap!

    BZzap! Senior Member

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    Check the specifications on your new tires for weight. Weight can affect the MPG just from rotational inertia increase. Stock LRR tires on the Prius are in the neighborhood of 18lbs. Say you install tires that come in at 21lbs, you can expect a loss in fuel economy from shear weight increase. Also, new tires almost always have higher rolling resistance until they are broke-in. Additionally, even a slightly more aggressive tread pattern can affect your mileage. Give the tires a little time to adjust and hopefully your fuel mileage will slowly return to an acceptable trade-off.
     
    Bay Stater likes this.
  4. Seekerhiker

    Seekerhiker Junior Member

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    I just tested my 2012 Prius vs my 2008 Prius on the same route using Hybrid Assistant. The takeaway is that the 2012 (has had software update) uses the electric motor much less than the 2008. It rarely exceeds 50% of its power, but often contributes nothing or just a couple kw.





    Posted via the PriusChat mobile app.
     
  5. Grit

    Grit Senior Member

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    Your gen 2 yielded 12 mpg while the gen 3 at 51 mpg an same route? I'd be concern with the gen 2 for sure.
     
  6. Seekerhiker

    Seekerhiker Junior Member

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    You must not have had the volume on. I was narrating. The mpg calculation was not at all correct for the Gen 2. Something was wrong. It was 25% or 20% of reality. The app is buggy.
    Posted via the PriusChat mobile app.
     
  7. Grit

    Grit Senior Member

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    20% of what?