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2012 Prius C 10k mile oil analysys

Discussion in 'Prius c Care, Maintenance and Troubleshooting' started by Mr Incredible, Dec 12, 2012.

  1. Mr Incredible

    Mr Incredible Chance favors the prepared mind.

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    Did my 10k mile oil change last weekend and here's the analysis report. I did prior changes at 1500 and 5k miles, with a report on the first.

    I was so busy watching the oil come out and looking at the color that I forgot to take a sample. I took one anyway from the pan, dipping from the middle. I keep the pan pretty clean so it didn't appear to make enough difference to tell. Blackstone didn't think so, either.

    I use Mobil1 0w-20. It takes almost exactly 4 qtrs to get the oil level to the full point. I purchase by the 5qt jug so have to finesse the final bit. I don't stress over it. A little over isn't going to kill anything.

    I used zero on the 5k mile interval. The oil still had color other than black, so may try 10k miles next time. It will be the first time I've done that. I don't see a problem with changing early, myself, and I may get bored and change at 7.5k.

    I think this is the cleanest little motor I've ever had.


    Prius C 10k mile report.JPG
     
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  2. PriusCamper

    PriusCamper Senior Member

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    It's likely you'll find a noticeable decline in MPG if you overfill your car with even just alittle too much engine oil. If you always overfill you can expect your throttle body to get gummed up and damaged, as well as possibly shorten the lifespan of your catalytic converter... PriusChat is loaded with threads of people dealing with diagnosing the red triangle of death simply because the oil change people always put four quarts rather than 3.5 quarts, which is the standard.
     
  3. firstrival

    firstrival Member

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    How did the report look at 1500 miles?

    EDIT: Nevermind! I see the second column.
     
  4. Mr Incredible

    Mr Incredible Chance favors the prepared mind.

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    Four quarts brings it right up to the full mark. The C, I believe, requests 3.9qt in the manual. To put in an entire .5 to 1 quart extra would be tough to do even with the jug and a funnel. I checked this morning and had about 1/32" over the full mark. The last oil change was 1/16-1/8th over the mark. Neither resulted in a noticeable decline in mpgs, and got my 61mpg tank with it slightly over the full mark. Some day I'm going to buy quarts instead of the jug and see what that winds up being.

    I think it would require quite an overfill to result in real problems. I realize that such a small engine and sump wouldn't take much, but a few oz's isn't gonna hurt (in my experience.)
     
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  5. PriusCamper

    PriusCamper Senior Member

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    I wonder if Toyota increased engine oil displacement to address this issue? Toyota dealers have insisted on putting in 4 quarts even when displacement calls for 3.5 quarts... There's lots of reasons for this I guess...

    It's kinda interesting the that a Prius C is smaller in so many ways, yet bigger when it comes to engine oil.
     
  6. Mr Incredible

    Mr Incredible Chance favors the prepared mind.

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    Copied from the owners manual: (Yay, I remembered something!)

    Oil capacity (Drain and refill)
    Without filter 3.6 qt. (3.4 L, 3.0 Imp.qt.)
    With filter 3.9 qt. (3.7 L, 3.3 Imp.qt.)
     
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  7. Mendel Leisk

    Mendel Leisk Senior Member

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    When the manufacturers put two marks on the dipstick, I think implicit in that is mid-way between those two marks is the sweet spot. That's in a perfect world, with an engine not consuming any oil. FWIW, no dealership's service department will agree with that. They treat the full mark kind of like a lot of drivers treat the speed limit: a starting point.

    Anyway, I like when the level's around the 3/4 mark, a bit below the full mark, but a ways to go before you need to be concerned.

    FWIW, the previous fill I did I was more-or-less on the full mark. And the latest fill I managed to keep it about 3/8" lower. Didn't seem to be any significant change in mileage. I'd suspect it would take gross overfill, say at least a quart (liter) before you'd start to notice anything.
     
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  8. Mr Incredible

    Mr Incredible Chance favors the prepared mind.

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    We see the world differently, then. When I see a full mark, I see it as a full mark. Full is correct when there is a range and no contra-indications. Fill to full. Not less than full. Nor greater than full. Full is the desired point of fill.

    (Something like the operating instructions for the Holy Hand Grenade of Antioch.)

    In Mr Incredible-land, at least.
     
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  9. xs650

    xs650 Senior Member

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    +1
    Three reasons for filling to the full mark.
    1. If something goes wrong and your engine starts to consume oil fater than normal, you have more time before it turns into a disaster.
    2. More oil means more additives and more oil to wear out, important for long change intervals.
    3. More oil means more time in the pan which gives a little help to oil cooling.
     
  10. PriusCamper

    PriusCamper Senior Member

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    More oil also means more likely a customer will not complain about not getting enough oil...

    But as someone who saw mpg drop because of too much oil, I'll do all I can to keep the oil level in the center of the sweet spot... Favorite part about Prius is all the wasy to fine tune the car and optimize as much as possible every sweet spot.
     
  11. PriusCamper

    PriusCamper Senior Member

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    Many threads on Prius Chat suggest that even just a 1/2 quart over can create problems...
     
  12. Mendel Leisk

    Mendel Leisk Senior Member

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    From the dealership service department's perspective it does make a lot of sense to fill to the top line:

    They don't know if the engine's consuming oil, and any customer who's paid the bucks for an oil change is going to be upset if they have to top it up shortly. OTOH, for DIY'rs...
     
  13. strongbad

    strongbad Member

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    Usually, pulling the sample from the pan invalidates the results. I've seen really bad reports from people who tried it, but your sample is the exception. Your iron is only 1ppm/1000mi which is as good as it gets. Nice.
     
  14. kammssss

    kammssss Member

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    I've been using 4 qts., which slightly passes the full mark, for 226k. Not a damn noticeable difference. No need to worry people.
     
  15. jayman

    jayman Senior Member

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    Very good used oil anlysis numbers. I used to post my results and as long as you properly break-in your Prius and switch it over to synthetic before 10,000 miles, the motor will run a long time with little to no oil consumption.

    Even keeping the oil level halfway between fill and full, I still had some gunk on the throttle plate and deposits on the mass air wires. I blame that on short trip operation. My FJ does the same thing unless it is always on the highway.

    The first two oil changes I had done at the dealership and they always managed to dramatically overfill the oil. Half an inch over the full mark
     
  16. Ryephile

    Ryephile The Technophile

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    Thanks for sharing the UOA, looks good. IMO there's no need to change it for another 10k miles.

    Just for clarification, you're using Mobil1 0W-20 AFE?
     
  17. Mr Incredible

    Mr Incredible Chance favors the prepared mind.

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    This is what I have been using, yes. I'd like to do another one or two 5k mile runs to watch the numbers go steady, then maybe try a 5w-20 to see what happens to the oil and the mpgs, if anything.
     
  18. Ryephile

    Ryephile The Technophile

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    Your wear metals are already excellent and on par with Blackstone's Universal Averages, which means the engine has stabilized and is broken-in. The additive package looks to be good-to-go for quite a bit more distance. I see no reason to do short intervals anymore unless you just want super-extra piece of mind.

    What would 5w-20 get you other than more friction when warm [cold]? You're not doing track days with the car so your oil temps aren't higher than typical, and you don't live in a hot climate to rationalize thicker oil. I'm just curious as to your rationale or proof; if I'm wrong let me know.
     
  19. xs650

    xs650 Senior Member

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    5W-20 has more drag when cold. When at operating temperature it acts the same as 0W-20.
     
  20. Mr Incredible

    Mr Incredible Chance favors the prepared mind.

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    It really doesn't bother me about the mpgs maybe taking a hit. I doubt they would be much more than background noise. There isn't all that much difference between the two, really, and I want to see for myself.

    When taking into account the large viscosity allowance in other countries, I'm not worried about any issues developing in the short step to a 5-20.