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Any Gen 4 Owners Out There With Blown Head Gasket ??

Discussion in 'Gen 4 Prius Main Forum' started by AmazingFacts, Jan 14, 2022.

  1. AmazingFacts

    AmazingFacts Member

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    I'm curious if anyone with a gen 4 has had to replace their head gasket. If so, how many miles on your Prius?
    I'm assuming there will be less head gasket issues considering the many improvements Toyota has made to the engine from gen 3 to gen 4.
     
    #1 AmazingFacts, Jan 14, 2022
    Last edited: Jan 14, 2022
  2. Colorado Boo

    Colorado Boo Active Member

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    I haven't heard of a single one. I think the CarCareNut on youtube is having a livestream later today, it would be a good question to see if he's seen any. (Master Toyota Technician at a dealership in Chicago.)
    Today, he posted a video of a 10-year old Camry that only has 166,000 but is burning oil bad and has other serious issues...car is toast and is the victim of owner neglect...only changing the oil yearly at 10,000 miles and you can see how dusty the engine compartment is...nobody's been taking care of her...I hate seeing that.
     
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  3. bisco

    bisco cookie crumbler

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    isn't 10k the interval?
     
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  4. Mendel Leisk

    Mendel Leisk Senior Member

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    There may have been one report here? But it was either false alarm, or there was extenuating circumstances?

    Gonna be crickets?
     
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  5. Colorado Boo

    Colorado Boo Active Member

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    No, if you really want your Toyota engine to last a long time AND not start burning the best interval is every 6-months or 5,000 miles, whichever comes first. I've seen Toyota engines who's owners only did oil changes every 10,000 miles and they started having problems around 150,000 miles...starts burning oil, doesn't run good, etc. Every car I've seen that's lasted 250,000+ had owners who changed every 5,000 or even 3,000 miles. (A new engine is thousands and thousands while an oil change is around $30 if you do it yourself...$40-50 somewhere else.)
    Anyway, the Toyota mechanic answered me...y'all are going to love this:

    Have you seen a Gen 4 Prius needing a head gasket or one burning oil? Not yet on the 4th generation. Honestly the 4th generation is really doing well. Examples with 200k have surfaced and nothing, they run well.
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    Significant changes I can think of on 4th gen engine:

    1. Revised EGR
    2. Plastic sleeves in the block
    3. Higher tension piston rings (this one's a bit of a "ringer" I think, since mid-way through 2014 model year the 3rd gen engines got revised, higher tension piston rings as well)

    IIRC the revised EGR was actually touted by Toyota, in some of the early sales blurbs. This seems an oddly technical topic for glossy brochures.

    My money's on the 3rd gen vs 4th gen EGR, as THE reason the fourth gen head gaskets are faring so well.
     
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  7. ChapmanF

    ChapmanF Senior Member

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    At the same time, there was an entire new engineering chemistry for EGR that was developed in the time between Gen 3 and Gen 4, and they adopted that for Gen 4, and many of the differences in the system are directly attributable to that change, which also has a good possibility of being what they were talking about in those blurbs.
     
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  8. AmazingFacts

    AmazingFacts Member

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    Good to know of all the revisions on made on the gen 4 engines. Hope the revisions have fixed the head gasket issue. We'll see as people rack up miles.
     
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  9. BettyWht

    BettyWht New Member

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    Good morning! New here and have a questions about your intervals. My '17 is creeping on 150k, and the first owner did oil every 5k miles and noted it in the manual so I continued the trend. Ive never been a fan of the 10k intervals on vehicles due to working at BMW and watching those fail time and time again, so regardless I was going to change every 5k. That and all my miles are highway.

    However, I did switch recently (2 o/c ago) to the mobil1 extended performance high mileage 0w20 with the high mileage filter, which boasts a 20k interval. I'd never wait that long, but I did give it about 9k miles between. The difference in cost of oil and filter is a whopping 5 bucks in parts and I get free labor, but I wanted your opinion on sticking to a 10k interval and if you had any experience with this oil. Oil wasnt very dirty at the last change, but at the 5k intervals with regular mobil1 0w20 it could have passed for new.

    I plan on hitting 1 million miles so Im doing everything I can to get there as inexpensively as possible. Thank you!
     
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  10. DOHCtor

    DOHCtor Member

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    Working for a Toyota dealership here. Personally, headgaskets failure is not what worrries me on my Prime as much as that exhaust heat trap/front pipe that leaks coolant like crazy.. we changes 3 or 4 per year.. at something like 1500+$$ each..
     
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  11. Mendel Leisk

    Mendel Leisk Senior Member

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    That doesn't sound good. Is that a rubber hose, or a metal pipe, an integral part of the exhaust heat recovery component?
     
  12. Georgina Rudkus

    Georgina Rudkus Senior Member

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    Isn't this welded to the back of the second catalytic converter? 9fd0079df4c4cdfe255e2617ee79851a.png
     
  13. Khantroll

    Khantroll Junior Member

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    This is actually what happened to me. That pipe leaked coolant into the exhaust, causing the engine to overheat and my head gasket to blow. The repair bill came out to about 1900, but I had literally bought the car 20 miles before that happened. The dealership had to repair it.

    It had about 100k on it.
     
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  14. ColoradoBoo

    ColoradoBoo Senior Member

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    Personally, I don't use those "high mileage" motor oils. If an engine, even old with a lot of miles, is running good, I'm not going to risk adding anything that might change the composition of the internal seals and gaskets. My philosophy is, "If it ain't broke, don't fix it."
    At the car store recently, saw an oil filter that says it lasts for 20,000 miles....that's beyond insane.
     
  15. JC91006

    JC91006 Senior Member

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    Well the "if it ain't broke, don't fix it" thing doesn't really work with Gen3 cars. Because if you just drive it until it reaches high mileage, it'll break and you'll need a new engine. But generally, I like to use that philosophy as well.

    20,000 miles on an oil filter? I think it would be ok on a new engine with 10,000 miles on it. A bit risky to do that with an engine with 100k miles on it.
     
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  16. Storm88000

    Storm88000 Active Member

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    I agree with you. 20k miles is asking for it. I don’t care what Mobil says on the packaging, oil gets dirty - the filter can only get so dirty (that’s why a used filter weighs 2-3x the weight of a brand new clean one) - and after awhile it’s not going to be filtering the oil and you are running dirt.
     
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  17. Ultimate_Combination

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    Uh oh!
    I've long gotten rid of my Turd 3 and occasionally check the Gen4 forums to stay up-to-date incase I find a deal on one- and my-oh-my; could this be something that should be sticky'd on the front page for a potential issue w/ this generation? :eek:
     
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  18. AmazingFacts

    AmazingFacts Member

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    Betty, I would certainly change the oil every 5k miles vs 10k, and use regular 0-20 Mobile 1 (not the high mileage w/ additives).
    And DOHCtor, thanks for your feedback. Could you shed more light on the exhaust heat trap/front pipe leak? Is it due to a crack or seal leaking?
     
    #18 AmazingFacts, Feb 12, 2022
    Last edited by a moderator: Feb 13, 2022
  19. orenji

    orenji Senior Member

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    Gen3 with 122k miles, 5k mile oil change interval and using Mobil 1 0W-40 as used in some other parts of the world. No oil usage.
     
  20. Khantroll

    Khantroll Junior Member

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    Well, take this with a salt shaker, but the mechanic who worked on mine said that it isn't uncommon for that happen. He said that sometimes people catch it due to dripping or white smoke, but if not it causes a head gasket issue.