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Excessive oil consumption: Does using thicker oil help?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Preeeus, Jan 9, 2019.

  1. Grit

    Grit Senior Member

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    It never gets below 25 degrees here, 10w will work for me.
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    If I was going to switch (from 0W20), 5W30 looks interesting. The 2nd gen spec'd oil in North America.
     
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  3. Preeeus

    Preeeus Member

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    Thank you for that reference! Is that from Australia (or Austria?)?

    Is it the same exact engine and other components that could be affected by oil viscosity?

    Are we reading it correctly, that if the weather is anything but well below freezing (anything above -7 degrees Celsius), they are saying it's acceptable to use 20W-50??? That's a huge difference in viscosity from 0W-20!
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    Hah, guilty of confusing abbreviation: Australia. I would strongly suspect the engine is identical. And yes, that's a much more traditional Owner's Manual statement.

    This stuff is all readily available btw, just google Toyota Australia. It'd be interesting to see what the 4th gen recommendation is.
     
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  5. Dxta

    Dxta Senior Member

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    What!
    You want to blow the engine isn't it?
     
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  6. Preeeus

    Preeeus Member

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    Assuming they were joking (hopefully).
     
  7. Dxta

    Dxta Senior Member

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    I don't think its right to use 20W50 for a below freezing temperature.
     
  8. Preeeus

    Preeeus Member

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    Ya, if we're reading that chart correctly, the cutoff for 20W-50 is -7 degrees Celsius, which is not too far below zero.
     
  9. Dxta

    Dxta Senior Member

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    Wao! Would reread it again then
     
  10. Preeeus

    Preeeus Member

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  11. Grit

    Grit Senior Member

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    CARB states led the way to max out efficiency so it pushes the standard to lower oil viscosity without factoring in maximizing engine life. “Use less gas” is their priority, they can care less about prolonging engine.
     
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  12. Preeeus

    Preeeus Member

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    A balance is needed. Parts require energy to build, use precious metals such as platinum (catalytic converter), and hit the pocketbook real hard. We're all for saving fuel and money (that's what we were thinking when we bought the Prius), but the entire environmental and pocketbook cost must be factored in.

    Right now, we're saving some fuel by owning a Prius, but are burning up oil like crazy, and are exposed to costs we can't afford.

    Don't want to get too far off topic, but wanted to reply. :)
     
  13. capolihu

    capolihu Member

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    I also read somewhere around the net that the guy was really keen on this topic and asked for lab tests after every oil change and found out that 0w20 degraded lot more than the 0w40 which is also called heavy duty oil for probably the same reason.

    Toyota delarship said to me too that 1qt per 1000 miles is quite normal for 130k miles (though she did not answer when I asked back "what was your car's consumption"), and even if I went to the road doing their stupid test, they claimed even if it fails, they probably will offer a motor repair (replacing rings and stuff) for 5k. The warranty is only till 60k miles. I bailed off as that would be no option for me, I would rather do an engine replace if I knew a place close-by..

    Therefor I decided now to put a 0w20 now for a short 1k range, then change it and put the 0w40 as it proved to be working for @orenji and for the other guy I mentioned earlier. I think and EGR cleaning might also help, but I don't have a garage now.

    I'm also thinking that right after the short range, I should put a Motor Flush to it, but I'm afraid that would do nothing for the ruined rings, maybe would clean a bit the EGR part out, but possible hurt the Cat.

    any thought?
     
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  14. Preeeus

    Preeeus Member

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    Our thoughts are very similar to yours.

    We are going to work with Toyota to try to get something accurate in the documentation before the Prius hits 150K (currently, they have us documented as passing the oil consumption test).

    If the Prius fails, the dealership's head of customer care said she would help us get assistance from Toyota to help us resolve the issue.

    Depending on how that goes, we may have to start trying thicker oils and different additives/flushes/cleaners, going off what has been posted on PriusChat. We'll probably try thicker oils first, because that seems less risky. On the other hand, @Peter123 has had excellent results with cleaners.

    The Toyota dealership said we shouldn't be at risk for needing a new catalytic converter or O2 sensors, even with burning tons of oil, but, well, they aren't going to pay for replacing them if a problem arises. And on the Prius, you can't easily just replace the cat, you have to replace the whole pipe, which costs a small fortune.
     
  15. cnc97

    cnc97 Senior Member

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    This was the analysis on my last oil change. Mobil 1 0-20 in the car for 5200 miles.
     

    Attached Files:

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  16. Grit

    Grit Senior Member

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    Great post. Towards the end, the filter wasn’t keeping up? Which filter did you use?
     
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  17. cnc97

    cnc97 Senior Member

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    Mobil 1. I use them because the plastic rings keep the pleats a set distance apart
     
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  18. capolihu

    capolihu Member

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    But you "fixed" yours didn't you? would be nice to see one with still ongoing problem, thought the results are predictable.

     
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  19. capolihu

    capolihu Member

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    I wish you luck, but I would not count on them :( They will probably give you a 5k price for engine "renewal"

     
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  20. capolihu

    capolihu Member

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    0w40 did not help, same quantity burned..
     
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