1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Will 50 psi tire cause any problems with my car?

Discussion in 'Gen 4 Prius Main Forum' started by rlecastro7, Jul 7, 2018.

  1. William Redoubt

    William Redoubt Senior Member

    Joined:
    Feb 13, 2016
    1,215
    1,164
    1
    Location:
    Coronado Island, California
    Vehicle:
    2016 Prius
    Model:
    Two
    You are, of course correct, but that's all behind the curtain. For the average owner and to summarize the functionality, the differential pressure turns on the light. That's the way Toyota TPMS works. Of course it needs the numbers to do the calculation. Thanks for supplying the detail.
     
    RCO and Merkey like this.
  2. Starship16

    Starship16 Senior Member

    Joined:
    Jun 8, 2018
    1,348
    1,453
    0
    Location:
    Beach Christmas
    Vehicle:
    2016 Prius
    Model:
    ----USA----
    I read a blog by Tony Schaeffer. Is that the same Tony, the founder of this website? He is in favor of higher tire pressure for a Prius. and gives all the pros & cons. He puts up a convincing argument.

    So my next dumb question is, what type and brand of tire gauge do you prefer? My new digital gauge shows the tires as being 3 psi lower than my new Milton pencil-style gauge. I've used the Milton gauges for 40 yrsrs.
     
  3. sam spade 2

    sam spade 2 Senior Member

    Joined:
    Mar 31, 2018
    7,035
    2,783
    0
    Location:
    USA
    Vehicle:
    2017 Prius c
    Model:
    Four
    The pressure listed on the side wall is "Maximum SAFE inflation pressure".
    Anything over that (cold) is NOT SAFE.
    This is not a difficult concept.
     
    RCO and Starship16 like this.
  4. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    7,041
    7,580
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    Thanks - that's where I read it - Tony says "Some have gone as high as 50/48 and continued to report even better overall mileage"

    The article:
    Check Your Tires’ Pressure » What Drives Us
     
    Starship16 likes this.
  5. kithmo

    kithmo Couch Potato

    Joined:
    Apr 25, 2010
    2,404
    2,773
    47
    Location:
    South Yorkshire, UK
    Vehicle:
    2016 Prius
    I find good quality dial type gauges seem to be the most accurate.
    I have one of these: https://www.google.co.uk/aclk?sa=l&ai=DChcSEwjx27zE7pHcAhUNOhsKHdJHB4QYABAJGgJ3bA&sig=AOD64_0RCRSQTZQPlJdpkiiZm1M6tHSrtQ&ctype=5&q=&ved=0ahUKEwi-urjE7pHcAhXPbVAKHY5iDS0Qwg8IRw&adurl=
     
    RCO and Starship16 like this.
  6. Starship16

    Starship16 Senior Member

    Joined:
    Jun 8, 2018
    1,348
    1,453
    0
    Location:
    Beach Christmas
    Vehicle:
    2016 Prius
    Model:
    ----USA----
    Correction. It was Danny Cooper who started Priuschat. Great website.

    Now everybody go check your tire pressure. ;) (I'm not touching mine. 199 mpg is good enough.)
     
    #46 Starship16, Jul 9, 2018
    Last edited: Jul 9, 2018
    RCO and alanclarkeau like this.
  7. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,327
    15,111
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    This extraordinary claim would require extraordinary evidence, not supplied here that I can see. The TPMS has alarm thresholds in gauge pressure and the warning light comes on if any pressure goes below threshold, or, directly to the point, even if all four pressures go below threshold, which would not trigger a "differential" alarm.

    The typical cause for a single pressure dropping would be a leak in one tire. For all four dropping together, the typical cause would be a large drop in outdoor temperature, such as that between Indianapolis and Dayton, OH six days ago, which turned on my TPMS light despite all four pressures staying quite close to each other.

    -Chap
     
  8. CooCooCaChoo

    CooCooCaChoo Active Member

    Joined:
    Jan 7, 2015
    888
    494
    0
    Location:
    Cow-lee-fornia
    Vehicle:
    2023 Prius
    Model:
    LE
    Yeah, outside temp is gonna affect the pressure. I like to set mine at around 1am after its been sitting all day. A couple of degrees from the coldest time of night isn't a big enough difference, but the temperature difference between night and day is too much.

    After that I just leave it, I like to check once a month though.
     
  9. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,123
    10,049
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Actually, no, my tires don't say that. In fact, a quick sampling of all four vehicles parked in dad's yard (where I am working now) at this very instant, finds NONE with that wording.

    At the moment, my Prius is the only one of wearing tires rated for under 50 psi. Its other tire set (I swap based on season, and it was shod with that other set a couple visits ago) is rated for 50.

    Reading the actual tire sidewall labels, without adding your own words -- even emphasized, at that -- is not a difficult concept. Among four different tires sets, I'm seeing three distinct wordings, NONE of them including that word you emphasized.
     
    #49 fuzzy1, Jul 9, 2018
    Last edited: Jul 9, 2018
    kithmo likes this.
  10. Starship16

    Starship16 Senior Member

    Joined:
    Jun 8, 2018
    1,348
    1,453
    0
    Location:
    Beach Christmas
    Vehicle:
    2016 Prius
    Model:
    ----USA----
    My sidewall says: MAX Pressure 44 PSI. Michelin website says that number corresponds to the maximum load limit. Whatever! I don't claim to understand it, and you can argue all this psi stuff until the cows come home. :LOL: The Priuschat Tire Pressure Wars! The conservative 36 psi boys vs the wild 90 psi dudes!

    All I know, is that my Prius rides like an old stage coach If I exceed any pressure over 41, or abouts. It feels and sounds like I'm driving a '65 Chevy pickup! And all the crappy roads around here sure don't help. Good luck!
     
    #50 Starship16, Jul 9, 2018
    Last edited: Jul 9, 2018
    RCO, kithmo and Merkey like this.
  11. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,732
    38,257
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I harp on about this: significantly higher pressures will transmit more road shocks to the suspension and bearings.
     
    Merkey likes this.
  12. wjtracy

    wjtracy Senior Member

    Joined:
    Sep 19, 2006
    11,314
    3,588
    1
    Location:
    Northern VA (NoVA)
    Vehicle:
    Other Hybrid
    Model:
    N/A
    I agree...Prius all have the "active" TPMS system which has the TPMS sensor in each tire continuously reporting Pressure and Temperature, which is pretty cool data if we could only see it like many other cars can see the TPMS data readout without a special tool.

    The "passive" TPMS system - which is not used in Prius and seems less common these days - is where individual tire RPM is monitored and a delta RPM implies that a tire is low. I believe early Volts had the passive system, and some pre-2006 Toyota's had it.
     
    #52 wjtracy, Jul 9, 2018
    Last edited: Jul 9, 2018
    Merkey likes this.
  13. VTBIGDOG

    VTBIGDOG Active Member

    Joined:
    Dec 21, 2016
    211
    146
    0
    Location:
    USA
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Get a Scangauge and then you can see all tire pressures.

    Posted via the PriusChat mobile app.
     
    Fester likes this.
  14. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,123
    10,049
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    But only after a certain firmware revision that went into production earlier this year. Before that, late last fall, it was made available for those who sent their units in for an update, and a number of us took advantage of the offer.
     
    #54 fuzzy1, Jul 9, 2018
    Last edited: Jul 10, 2018
    Merkey likes this.
  15. wjtracy

    wjtracy Senior Member

    Joined:
    Sep 19, 2006
    11,314
    3,588
    1
    Location:
    Northern VA (NoVA)
    Vehicle:
    Other Hybrid
    Model:
    N/A
    I can see the pressures/temps with Techstream, but it would be nice to have it on a utility screen of the vehicle
     
    Raytheeagle likes this.
  16. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,476
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    Buy a Lexus, the pressures are there(y).
     
  17. wjtracy

    wjtracy Senior Member

    Joined:
    Sep 19, 2006
    11,314
    3,588
    1
    Location:
    Northern VA (NoVA)
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Re: TPMS - On my *other* vehicle I just had a near blow out on the highway when my TPMS valve stem broke spontaneously. The tire place said the TPMS on some of the Dodge/Chrylers (minivans etc) have been corroding due to road salt etc. I was lucky the valve still held some air in, and the TPMS light came on allowing me to get to the exit to install a compact spare.

    We are lucky the Toyota TPMS are more robust, and you just gotta wonder if TPMS is a good thing or a bad thing overall. In theory very good to keep tires inflated but how many accidents/repairs are they causing?
     
    #57 wjtracy, Jul 10, 2018
    Last edited: Jul 10, 2018
  18. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,732
    38,257
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    That's irony personified.
     
    RCO and alanclarkeau like this.
  19. RCO

    RCO Senior Member

    Joined:
    Aug 31, 2016
    3,709
    5,183
    0
    Location:
    Cornwall
    Vehicle:
    Other Hybrid
    Model:
    N/A
  20. kithmo

    kithmo Couch Potato

    Joined:
    Apr 25, 2010
    2,404
    2,773
    47
    Location:
    South Yorkshire, UK
    Vehicle:
    2016 Prius
    Race X Professional Tyre Pressure Gauge RX 0014 £10.99
     
    RCO likes this.