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Maximum PSI ?

Discussion in 'Prime Main Forum (2017-2022)' started by Rob43, Sep 12, 2019.

  1. randerson9248

    randerson9248 Junior Member

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    You don't have any PROOF that my experience is FOLLY.
     
  2. eatriceyo

    eatriceyo Member

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    i pump my stock tires up to 38 psi cold and feel like a risk taker
     
  3. sam spade 2

    sam spade 2 Senior Member

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    Sure I do. You provided it.
     
  4. Rmay635703

    Rmay635703 Senior Member

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    with around 1 million miles on slightly overinflated tires I can say that you tend to exaggerate on this subject.

    I started overinflating during my years of towing and craft sales when I discovered it ended my constant sidewall failures despite being at sidewall rating and under the weight rating.

    I would argue under most circumstances 50% overinflated is however pursuing diminishing returns and a waste of time but the likelihood of him flying off the road is much lower overinflated than under inflated.

    under inflation is the most dangerous thing anyone will do but is completely ignored and sometimes recommended for a better ride at the expense of sidewall failures/blowouts

    in the real world consequences of overinflation can be more frequent tire punctures and early suspension wear which are worth noting but not an immenent danger by any stretch

    on my Volt which is notorious for 12,000 mile to sidewall failure OEMs I got 80,000 miles on the set running most of the time at 60psi with drops in pressure only during snow or off road operation. The tires were only 51psi rated but handling was much firmer/precise a tad beyond.
     
    #65 Rmay635703, May 30, 2020
    Last edited: May 30, 2020
  5. fuzzy1

    fuzzy1 Senior Member

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    Yup. His OEM tires lasted only 80k miles, his spark plugs lasted only 100k miles, and his wiper blades needed replacement not just once, but twice! All proof that he is engaged in folly. Uh huh.
     
  6. ice9

    ice9 Active Member

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    From your first link: "This same decrease in contact surface (from over-pressure) can also cause a drop in mpg, as the engine now has to work harder to compensate for the reduced contact patch."

    ???

    The 2nd and 3rd links make sense.
     
    Mendel Leisk likes this.
  7. GabrielD

    GabrielD Member

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    Ok, I have specification provided by tire manufacturer and by Toyota factory (on the door).
    I think the tire manufacturer is better choice.
    In first picture is Toyota factory stick on my door.
    They say to inflate only when car is full with 7 persons at 2.3 bar.
    I usually run with 2.5 even I drive only myself. What I am trying to say there is no general rule about tire inflation pressure, no formula...
    People must try and find the best result regarded to themselves.
     

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  8. sam spade 2

    sam spade 2 Senior Member

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    No I don't.
    I have NEVER made a post that is critical of a "slight" over inflation. None, nada, zip.
    It appears that you tend to remember things that never happened.

    He is putting 65 in a tire that is likely rated for a max. of 45.
    That is 45% over. There is no way that is a defensible action.
     
  9. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah a little puzzling. It's harder to move something with the
    Well, this is what Michelin says:

    upload_2020-5-31_6-37-58.png

    From the following web page:

    How to check tire pressure | Michelin Canada
     
  10. GabrielD

    GabrielD Member

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    With all due respect, but I think Michelin is wrong on this one.
    I will respect what the producer of the tire says.
    How would a car can go smooth if I am using some tires very thick that need extra psi than usual?
     
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  11. Mendel Leisk

    Mendel Leisk Senior Member

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    Paging @Grit
     
  12. sam spade 2

    sam spade 2 Senior Member

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  13. GabrielD

    GabrielD Member

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    Thank you for correction, Sam.
    I am confusing terms "thin and thick". But the idea is the same, you have to follow the producer of tire instructions, not Michelin.
    Only in case they coincide...
     
  14. sam spade 2

    sam spade 2 Senior Member

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    But Michelin IS a producer of tires and tire instructions.
    A BIG one with an excellent reputation.
    I don't understand what you are trying to say.
     
  15. GabrielD

    GabrielD Member

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    Well, I know Michelin is one the best producers of tires.
    But how would they know what other producers tires need to be inflated?
    One producer has thin, others thick, for sure they cannot use the same pressure.
    And about label on the door, is available, ONLY when you use factory tires. I think they are not Michelin on Toyota cars.

    Later edit:
    Here are Michelin reccomandations about tire pressure... they say to check with owners manual... not with tire's wall...
    But what if I change tire? other than factory?
     
    #76 GabrielD, May 31, 2020
    Last edited: May 31, 2020
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Toyota vehicles typically have a variety of tires, from the factory. Obviously the same spec's/size, but often from several manufacturers. There are no specific "factory tires", they're just tires, you could buy them yourself. And the recommended tire pressure remains the same.

    Your vehicle is the same as North American Prius v I think? North American Owner's Manual says this:

    upload_2020-5-31_11-35-42.png

    Also, it's worthwhile to check the accuracy of your pressure gauge. Simple/cheap way is to get multiple gauges, and see if they all agree. If most do, they're likely to be the accurate ones. My current favourite gauge, easiest to use/read, reads 3 psi higher than accurate, judging by others I have. So I set pressure 3 pounds high, by that gauge.
     
  17. GabrielD

    GabrielD Member

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    You are right, it is a Prius V.
    And the label on the door says all 4 wheels have the same pressure.
    But, you are right, Toyota have a diversity of tires, and I think it is not logical to use the same pressure (on label or manual) for different tire manufacturer. Maybe one special tire will be invented this year and needs a pressure different than label...
     

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  18. sam spade 2

    sam spade 2 Senior Member

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    Now I see.
    You are under the mistaken impression that tires of the same size and general design are VASTLY different if made by different companies.
    THEY ARE NOT.
    Unless they are made for some special purpose, different brands of tires are more alike than different.
     
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  19. Mendel Leisk

    Mendel Leisk Senior Member

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    With respect, I don't think what you're saying is logical. Think it through: did they set that pressure on the decal for one particular tire? If so which one? And don't you think they'd disclose that?

    Nope. They recommend a tire spec and a tire pressure. And the tire manufacturer very likely all agree with that pressure. I've quoted Michelin so far. If you want I could track down and quote others. Or let go?
     
    ice9 likes this.