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The verdict on increased oil weight?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Higgins909, Sep 2, 2021.

  1. Higgins909

    Higgins909 Member

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    Does anyone have a verdict on increased oil weight? I have a 2010 with 185k and I think I've put 3 quarts of oil in so far and I'm only at 4k on this oil change. If I need more oil before the 5k I plan on changing it. But increased oil weight is something I've been wondering about. Looking around 0w30 might be heard to find. 0w20 is stock. I can find 5w30 and 10w30 but I wasn't sure about changing the cold number. All are full synthetic.

    I have concluded that my short 7 mile trips to and from work are burning oil faster then a 300 mile road trip. I live in Texas where summers can be 103F and the last winter was apparently 9F. The googling of 0w20 doesn't line up with the Prius manual, the temperature range that is.

    Thanks,
    Higgins909
     
  2. AzusaPrius

    AzusaPrius Senior Member

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  3. PriusCamper

    PriusCamper Senior Member

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    Adding 3 quarts in only 4K miles means you need an engine swap... It will cost you more the longer you put this off. Your engine is about to die and you need to rebuild or replace it, preferably with a Gen4 used engine, but a gen 3 could work too...
     
  4. Higgins909

    Higgins909 Member

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    It was something I thought I would try. As a cheaper solution. I'm burning oil as it is. Have heard about it helping with 2000's vehicles. Recently watched a video that made me wonder as a ecoboost engine was being worked on. They upped the HOT number and it seemed to have worked.


    I've been wanting a new car for quite a while but I try to watch my money. The plan was when it died I would buy a new(er) one. The market is absolutely insane right now, more than it was before. The problem is by the time the engine finally dies, I will have already been messing with cells in the HVB or something of that nature. But that kinda sounds like a financially viable option, when the time comes. $3000-$4000 and I've got a car ready for many more years with a newer engine and possibly new HVB.

    I wonder where you find a engine. I've looked around a little bit and it gives a range. 2010-2018 45-55k miles. Nothing specific. If I was looking for a Gen4 engine. Right now it's not burning that much. The manual says 1.1quarts per 600 miles. For the most part, I think it's been burning this amount since I got it in 2017 with 163k on it. It will eventually destroy the cat(s) and sensors. If I could extend the life my putting in a slightly heavier oil, I'll do it. But it's looking like a no.
     
  5. sam spade 2

    sam spade 2 Senior Member

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    Maybe. But maybe not.......at least not yet.

    Seems rather strange to me that ALL of the major oil companies sell a "high mileage" oil formulation that goes up to maybe 10W40 or so if it is such a BAD thing to do. Hint: it isn't, under the right circumstances.

    It certainly won't hurt anything to give it a try and you might be pleasantly surprised.
     
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  6. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    An alternative would be a brand new short block (3rd or 4th gen?), have a machine shop go over the head, and supply them with Toyota’s gasket kit. Then reassemble with new head gasket (included in kit) and head bolts. Kit and bolt part no’s in attached.
     

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  7. douglasjre

    douglasjre Senior Member

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    0w40 Mobil 1 my friend
     
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  8. Higgins909

    Higgins909 Member

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    So, I would like to do a little update. I wish I changed oil weight a long time ago. You will lose MPG, but I now burn a lot less oil. Which has gotten progressively worse over time. Now at 201.5k miles. I currently run 10w40 with 20w50 as top off oil. It's also synthetic blend. Blend oil seems to have more viscosity over full synthetic, with the same oil weight. I finally got a catch can installed.

    My intake manifold has had a pool of oil in it for a while. I've only had the CC on for about 400 miles and have only caught, not even a tea spoon yet. I really want to do a B12 Piston soak but am scared of my #1 spark plug being stripped. Also the time needed and then risk.

    0w20 Full Syn various, drinks
    5w30 Full or Blend, not much difference
    0w40 Full Syn Mobil 1 Euro, better, but still thirsty
    10w40 Blend Castrol GTX High Mileage, best it will get.
    20w50 Blend Castrol GTX High Mileage for top off oil, just to test.
    Noticed less oil leaking from back side of timing cover.

    I do not recommend 10w40 in 30F or below temperatures.

    In about 2k miles, with about 300 of them being towing, I've only lost about 2.5 quarts. Which is pretty good, with how bad it's getting. I did a 400~ mile road trip and lost about 1.5 quarts on 0w20. Knew I needed to start trying things out before it got too late.
     
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  9. BiomedO1

    BiomedO1 Senior Member

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    My old 2012 Prius C used to burned a little over a quart every 10K mile oil change. I switch to 5w20 and the burn rate went down to a pint every oil change. I believe 5 wt oil is fine down to 0 F, but do your own research. I believe Toyota Prius manuals for other countries go all the way up to 10 wt oil on the cold side. Your heading into the hot summer months, so I would experiment a bit. The point is small adjustments can have a major impact in your oil consumption, besides you know your going to have to fix your engine sooner or later. Also stick to the same brand of oil - they all behave a bit differently when hot and cold cycled, you don't want to taint your results and try to eliminate as many variables as you can control.

    Just my 2 cents....
     
    #9 BiomedO1, May 18, 2024
    Last edited: May 18, 2024
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  10. Cadenza

    Cadenza Member

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    HybridPit engines $2100-$2900: Toyota Prius Performance Parts

    Main battery at a local SoCal dealer $2200: 2010-2011 Toyota Prius Drive Motor Battery Pack G9510-47062 | Toyota of Anaheim Parts

    GreenTec re-manu main battery $1200: Toyota Prius Gen 3 Hybrid Battery Replacement | Greentec Auto

    Hopefully, we'll see Lithium upgrade readily available in the near future:


    In the meantime, I would try products like Liqui-Moly Proline Engine Flush or piston soak option like Berryman B12 Chemtool. Toyota's universal oil 0w-20 for all of the US and in all weather condition is really horse poop. In other markets, you can alternate oil grades according to the seasons. Toyota redesigned the the oil control rings somewhere during the 2014 MY...

    Original design with tiny middle spring:


    Re-designed rings with taller pleated middle ring:
     
    #10 Cadenza, May 26, 2024
    Last edited: May 26, 2024