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Gen 3 170k miles oil viscosity

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by MeGuinness, Jun 29, 2016.

  1. MeGuinness

    MeGuinness Member

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    So should I keep using 0/20 oil with this high milage or change to a different viscosity? What is best guys ? I'm in UK.
    Thanx
     
  2. tankyuong

    tankyuong Senior Member

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  3. tankyuong

    tankyuong Senior Member

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    I switched to 5w20
     
  4. Indy John

    Indy John Member

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    There is zero logic to switching from 0W anything to 5W anything. Experts agree that most engine wear occurs during the first minutes after cold start-up (e.g. 75 degrees F). There is currently no engine oil thin enough to lubricate properly at cold start-up, and 0W is currently the thinnest available. "W" indicates a different cold-weather test standard than regular testing, which is done at 212 degrees F, considered to be normal operating temperature. Mobil 1 0W-20 and 5W-20 have the same viscosity (measured in Centistokes - cS) at 212 degrees F, which if I remember correctly is 8.7.
     
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    Is the oil level dropping between changes? If so how much? And how frequent are your changes?
     
  6. CR94

    CR94 Senior Member

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    ... and what's the mileage on it now?
     
  7. MeGuinness

    MeGuinness Member

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    10k interval and yes the level goes down of about 60% in between, 170k miles!!
     
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  8. CR94

    CR94 Senior Member

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    So, if I understand correctly, it's consuming about 0.9 liter (1.6×60%) per 10,000 miles (or 10,000km?) ? That rate isn't so bad, if it's stable. Before the Prius, I never had a car that consumed that little.
     
  9. Mendel Leisk

    Mendel Leisk Senior Member

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    @CR94 I took "60%" to mean 60% of the spec quantity of oil: 4.2 liters or 4.5 quarts, about 2.5 liters loss.

    By "1.6" I'd assuming you're meaning the quarts between the two dipstick marks, another likely interpretation, and likely the correct one.

    @MeGuinness : Can you give a specific oil loss?
     
  10. CR94

    CR94 Senior Member

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    I agree that that was unclear. Either guess, or neither, could be right.
     
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