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Michelin Energy Saver A/S PSI for Prius v ??

Discussion in 'Prius v Fuel Economy' started by vForVictory, Sep 15, 2017.

  1. vForVictory

    vForVictory Junior Member

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    The Michelin Energy Saver A/S tires I just purchased for our Prius v have 51 PSI max printed on the sidewalls. In every thread on priuschat, other owners say they have 44 PSI max printed on the sidewalls. Questions:

    1) I know tires sizes are different between different models of Prius. Is PSI also different? Or is this a recent change for all Michelin Energy Saver A/S tires?

    2) Around 42/40 or so seems to be the favorite inflation pressure for the 44 PSI Energy Saver A/S discussed so frequently on this site. What is suggested inflation pressure for 51 PSI Energy Saver A/S for Prius v?

    3) In Prius v, how significant is gas mileage difference between the 35/33 pressure listed in manual and the 42/40 pressure so often suggested on this site?
     
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  2. bisco

    bisco cookie crumbler

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    good questions. i can only say that my energy savers purchased a few months ago are listed at 44 max, but they are 15". i have mine at 42/40, in hopes of better mileage, but realistically, can't observe a difference between that and recommended.
    i have never seen any scientific testing to back up the claims, but a lot of people will say they have seen a few gallon difference.
     
  3. bat4255

    bat4255 2017 Prius v #2 and 2008 Gen II #2

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    I run 38 psi, a compromise between comfort and mileage. mpg difference is about 2 mpg. Driving style, distance and temp. is a bigger factor
     
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  4. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    It is widely believed that Toyota's recommendation maximizes comfort.
    While the side wall pressure may well maximize MPG, I urge you to choose based on /tread life/safety/handling.
    My theory is that finding the pressure that gives the most even wear, is also the pressure that has the most grip. (I did find more difference in the gen 2 than the v)

    On my 2012 v Three, that has been 40/38 with my Energy Saver A/S tires. I put them on at 55,000 miles and am at 107,000 and will make it at least one more winter.
     
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  5. JamesBurke

    JamesBurke Senior Member

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    Michelin Energy Saver A/S P205/60R16 91V only has a max load of 1356lb @ 51psi. Same as the load rating of the Michelin Energy Saver A/S P215/50R17 91V found on the pkg Five with 44psi spec. We don't get load per psi data for passenger tires in the US so suggest using the %/psi increase method. Not less than Placard of course. Example: For 44 psi tires 32psi = 72%, 36psi = 82%, 40psi = 91%. For 51 psi tires your psi's would be 37psi = 72%, 42psi = 82%, 47psi = 91%. I would consider these the minimum psi increase.

    Toyo guide for tire load/psi tables
    https://toyo-arhxo0vh6d1oh9i0c.stackpathdns.com/media/2125/application_of_load_inflation_tables_20170203.pdf
     
    #5 JamesBurke, Sep 20, 2017
    Last edited: Sep 21, 2017
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  6. Mendel Leisk

    Mendel Leisk Senior Member

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    When there's a higher pressure on the sidewall tires are often designated "XL", for "Extra Load", have stiffer sidewalk, firmer ride. Not sure if that's the case here; you could look up the specs on TireRack.

    I would just start with the pressure that's on the drivers door decal (Toyota's psi recommendation), then try a few pounds higher.
     
  7. vForVictory

    vForVictory Junior Member

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    I looked up TireRack at your suggestion. They do show more info than most other sites:

    Michelin Energy Saver A/S | P205/60R16

    Click on specs and you can see that it does list 51 PSI max. I guess this was a recent change - or perhaps it's just different from the P195 which lists 44 PSI max.

    Thanks for all the advice everyone.

    Meant to put this in the Prius v section - sorry for putting it in the wrong section.
     
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  8. vForVictory

    vForVictory Junior Member

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    I decided to try 40/38. So far, I'm not noticing any difference whatsoever from 35/33, in terms of how the ride feels.
     
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  9. rdgrimes

    rdgrimes Senior Member

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    Differences in MPG relative to PSI will vary according to tire size and tire temperature. You should see the biggest gains at higher temps. Cold tires are bad at any pressure.
     
  10. vForVictory

    vForVictory Junior Member

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    We started with the default 35/33. A couple weeks ago raised it to 40/38. We have been unable to notice any difference at all in terms of handling or comfort. Will leave it here for another month or two at least but maybe we'll try a little higher at some point to see how that feels.

    Do people actually notice any difference between 35 and 40 on a Prius v?

    We are not aggressive drivers. In fact, being new to Prius, we may be going the other extreme as new Prius drivers tend to do in response to constant feedback on MPG . . . so I wonder if that's why we wouldn't hardly notice a difference between 35 and 40?
     
  11. Mendel Leisk

    Mendel Leisk Senior Member

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    Assuming you've got 65 profile tires, the difference between 35 and 40 IS pretty subtle. It's the low profile 45's that are more punishing, lol.
     
  12. vForVictory

    vForVictory Junior Member

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    Yes, we have the regular tire size for Prius v. Specifically, the Michelin model number is:

    P205/60R16
     
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  13. m.wynn

    m.wynn Senior Member

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    Although I'm in a Gen 3 liftback, agree with @JimboPalmer that 40/38 is the best of all worlds. After much "testing", or more accurately, "playing around with pressures", I found higher psi does not improve mileage but noticebly decreases ride comfort. This is likely due to deflection with regard to imperfect road surfaces, IMO. Much lower than that trends toward less even tread wear to go along with actually only slightly less mpg. Again strictly IMO, and I never go below ~37/35 on any vehicle.

    Energy Saver A/S 195/65/15 at somewhere around ~25k miles. Love these tires and love the X-ice 3's just as much in winter. As a cyclist, I've used their high-end road tires since the mid-80's. Michelin does good work.

    Sorry OP, for not directly answering your Q's, just offering general obsevations regarding an area I've spent some time playing around with.
     
    #13 m.wynn, Oct 17, 2017
    Last edited: Oct 17, 2017
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  14. AMP

    AMP April 2012

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    Just a reminder. New tires take a few hundred miles to break in. When they are new that can drop the mpg a little bit.
     
  15. vForVictory

    vForVictory Junior Member

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    Well - so far it's already better by around 2 MPG in the first 700 miles (up from around 35 MPG to over 37 MPG). Nice to know it will be ever better soon!

    Most of our driving is trips lasting less than 5 miles that are hilly and have stop signs and traffic lights. So we will only go over 40 MPG for a tank of gas when most of our traveling is non-local.