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Prius using oil - change viscosity?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by fikey13, Jan 14, 2013.

  1. fikey13

    fikey13 Junior Member

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    With a 120,000. miles on my Prius and having done fairly extensive research, I am faced with the fact that it is using a noticeable amount of oil. I have been convinced by 2 Toyota mechanics to "get over" the fact that I have never had a Toyota use oil and that it isn't worth the time and money trying to track it down, it just is. The service manager has also told me that they have had this happen with a lot of the hybrids and that part of it is the low viscosity oil. That being said, is there anything wrong with increasing the viscosity to reduce the amount of oil consumed? Years ago, we would use straight 30 weight in older engines that started to use oil.
     
  2. jadziasman

    jadziasman Prius owner emeritus

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    Last time you posted, you said your Prius was using about 1.5 qts per 5000 miles.
    Has the consumption increased since then or is it about the same?

    If it's been the same, then you will just need to check the oil level frequently and top it off
    when needed. Nothing wrong with that.
    Your oil consumption is not excessive considering the number of miles. Sure it could be lower but unfortunately it's not for some reason. And you might not be able to determine the reason - since there are so many to choose from.
    Keep using 5W30. And change the oil every 5000 miles.
    You could try high mileage synthetic oil to see if the consumption decreases. Might help, might not.My 2 cents - learn to live with it.
     
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  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Since you live in an area that has cold winters, I would not suggest you increase oil viscosity at this time. You may experience engine no-start problems with a heavier weight. If you want to try a higher viscosity oil during the summer, that would be reasonable.

    If in fact your oil consumption is 1.5 quarts per 5K miles, that is not unusual considering your car's odometer reading, and obviously the simplest and easiest approach is merely to add engine oil as necessary.
     
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  4. uart

    uart Senior Member

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    Hi fikey, what brand/grade oil are you currently using and have you used in the past?

    As other have said, 1.5 qts per 5000 miles is not all that bad. As long as you top off every few thousand miles it wont cause you any problems at all.

    I also recommend sticking with 5W30. Why don't you try a high mileage oil like Valvoline Maxlife.
     
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  5. sorka

    sorka Active Member

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    Wow! 1.5 qts every 5K miles???? My 2009 has 120K miles on it too and it doesn't consume a drop, at least according to the dip, between changes. I've never had to add oil.

    The only exception was using the B-mode coming out of Yosemite one weekend. It dropped about a 1/3 qt alone on that one trip. I've never used the B mode again.
     
  6. CBarr31

    CBarr31 Active Member

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    Hello fikey, my Ema is using about 1 qt. every 2000 miles so she burns a little too. There are several threads on here about high or higher mileage Prii burnig oil. I suggest doing a search and reading some of those they may provide some insight.

    I switched to Pennzoil 5W30 high mileage and it may or may not have helped the Burn. As Patrick (THE Guru) suggested I would not switch to heavier oil until spring/summer and if/when you do expect to see an MPG drop because of it. I think I may try this switch in late April or May but haven't decided yet.

    I set the Oil Reminder in the maintenance screen for 2,000 miles add a quart when it comes on, reset it, add another quart in another 2,000 miles and then do an oil and filter change when the "Maint" light comes on or within a few hundred miles.

    Good luck with your car.
    Chris
     
  7. wjtracy

    wjtracy Senior Member

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    if I have not already mentioned...you can try 5W-30 Mobil-1 High Mileage Formula...that gives you additives and other formulation features to retain oil in the car.
     
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  8. fikey13

    fikey13 Junior Member

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    I appreciate the feedback. I haven't been real particular about the brands I used. I know this will stir a lot of controversy, but I happen to be of the opinion that it wasn't the brand of oil that caused the problem. I have had many Toyotas and have used the same brands of oil and never have used a drop of oil.

    Do you really feel that changing to 10-30 oil will cause start issues? I am in Virginia, not Alaska.

    What does the "high mileage" oil have in it that would cause a difference?

    Dos using the "B" feature increase oil consumption?
     
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1. Regarding no-start issues, try it for yourself and see.
    2. Additional additives which are supposed to soften engine oil seals. If you do a web search on that, you will see considerable debate about whether that oil makes any difference. I suppose you can try it and see whether it helps or not, in your particular case.
    3. Definitely, since the engine is forced to rotate at a higher RPM than it otherwise would, for a given vehicle speed.
     
  10. Britprius

    Britprius Senior Member

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    As Patrick has the oils contain compounds that are supposed to soften and swell oil seals. They also contain products to free gummed piston rings and remove carbon deposits behind the rings.

    A few years ago I had a friend that had a car that was burning oil.

    I removed the cylinder head and re built it with new valves, valve guides and seals. After refitting the head we were to find that this only reduced the oil consumption by about half "better than nothing"

    A couple of months later my friend had the oil changed at a shop advertising cheap oil changes and his oil consumption was reduced a lot further.

    We could not work out why and I ask what oil grade he normally use 20w50 when we checked what oil had been put in the car at the oil change it was 10w30.

    The only way I can explain the improvement is that the piston ring can scrape the thinner oil of the bores easily and also return it through the small holes behind the oil control rings in the pistons than the thicker oil. Any suggestions?

    John (Britprius)
     
  11. wjtracy

    wjtracy Senior Member

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    According to the Mobil-1 brochure I have, they say the High Mileage has more seal and wear additivies to reduce wear. They also show it being a little less favorable (1-star rating vs 2-star rating) for low temp starts and MPG increase compared to the other Mobil-1 fomulas. So that either means the additives add a little viscosity or the base oil could be a little heavier to reduce oil leak tendency. I don't think its a magic bullet but I do think it really does contain some formulation differences to try to help minimize oil loss.
     
  12. uart

    uart Senior Member

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    At under 1qt per 3000 miles your priority should be more about reducing further engine wear than worrying too much about oil consumption. Just check it and top off regularly.

    The fact that you've always used "whatever's cheap" may or may not have contributed to the oil consumption. Without knowing exactly what oils you've used no one can know. If you're talking about name brand conventional oils (like castrol mobil valvoline havoline shell pennzoil for example) then you're fine. Any SL/SM/SN rated oil from any major oil company will protect your engine just fine for a standard 5k mile drain interval. If however you've been going with "off brand" dime store or flee market oils, then all bets are off. Sadly there are some truly woeful oils available that will damage your engine if you use them. See The Petroleum Quality Institute of America
     
  13. rwinkel

    rwinkel New Member

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    I don't get it. Why would using B mode increase oil usage?
     
  14. jadziasman

    jadziasman Prius owner emeritus

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  15. Mendel Leisk

    Mendel Leisk Senior Member

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    sorka may have moved on; he said that about 2.5 years back. Anyway: B mode invokes engine braking, would that mean high vacuum in the cylinder heads, and possibly sucking oil up through the piston rings, and then out the exhaust? Just a stab.
     
  16. rwinkel

    rwinkel New Member

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    [QUOTE="jadziasman, post: 2239735, member: 72054"[/QUOTE]
    Thanks! I had the wrong impression about B.