Was airing up after the end of a trail run and i happened to have the psi screen on. As the tire was filling, the gauge was actually measuring the change every ~5 seconds! Was able to use that to get all tires to proper level without constantly disconnecting air hose and checking with handheld gauge! Probably saved me 5minutes of measurement/fiddle time. So cool!!!
Instrument cluster tire psi monitoring
- Thread starter pchLC
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Yes, very nice. What year wagon?
I did a 5 wheel rotation a few weeks ago on my ‘18 LX and after doing the TPMS reset, and after a bit of driving, the system correctly identified the new locations of each. A mechanic friend of mine told me that generically speaking, early implementations of TPMS were not capable of this.
I did a 5 wheel rotation a few weeks ago on my ‘18 LX and after doing the TPMS reset, and after a bit of driving, the system correctly identified the new locations of each. A mechanic friend of mine told me that generically speaking, early implementations of TPMS were not capable of this.
On a related topic, my TPMS cluster PSI values are slighter higher by 2-3 PSI vs what my tire gauges indicate (I have tested with 3 quality gauges).
Could this be a result of running larger tires ( LT285/70R18 E 127/124Q Ridge Grapplers - set for 38 PSI) on the OEM wheels? Cluster display shows avg 41 cold tire.?
Could this be a result of running larger tires ( LT285/70R18 E 127/124Q Ridge Grapplers - set for 38 PSI) on the OEM wheels? Cluster display shows avg 41 cold tire.?
Correct, that's a new feature. My 13 doesn't do this.. it just shows the same 5 positions regardless of where they have moved to on the vehicle.
Tire size shouldn't matter, but what can is altitude, since the senders internal to the tires have no choice but to measure absolute pressure, vs the gauge pressure your hand-held is likely measuring. Technically gauge pressure is a better measurement, as it reflects how the tire will act in the atmospheric pressure surrounding it.
Here in central texas my dash reads ~2psi lower than my pretty accurate dial gauge.
Realistically, 2psi (or even 5, sorry gaijin) shouldn't matter. We generally aren't pushing the load or speed ratings of our tires, and even if we were the engineering overhead should still give us plenty of safety buffer.
Well... remember the Firestone/Ford controversy?
From Wikipedia (Firestone and Ford Tire Controversy):
The Firestone and Ford tire controversy was a period of unusually high failures of P235/75R15 ATX, ATX II, and Wilderness AT Firestone tires installed on the Ford Explorer and other related vehicles.
The tire failures are linked to 271 fatalities and over eight hundred injuries in the United States with more injuries and fatalities occurring internationally,[1][2] it led Bridgestone/Firestone and Ford Motor Company to recall and replace 23 million tires, it cut the market value of Bridgestone/Firestone in half,[3] Firestone closed the Decatur, Illinois factory where the tires were manufactured, several executives in Bridgestone and Ford resigned or were fired, it led Congress to pass the TREAD Act,[4] and it brought an end to the nearly 100 year corporate relationship between Ford Motor Company and Firestone.
Certainly, there was a lot of finger pointing back and forth between Ford and Firestone - I think we all remember that. But do you remember that Firestone's main defense argument was that Ford's RCTIP (Recommended Cold Tire Inflation Pressure) was too low? Care to guess by how much? 4psi!
More from the same Wikipedia entry:
On March 6, 2000 NHTSA began a preliminary inquiry[17] and on May 2, NHTSA began an investigation (PE00-020)[2] concerning the high incidence of tire failures and accidents of Ford Explorers and other light trucks and SUVs fitted with Firestone Radial ATX, ATX II, and Wilderness tires.[2] On August 9 Firestone recalled all ATX and ATX II tires and all Wilderness AT tires manufactured in Decatur, IL. On August 31, 2000 the Office of Defect Investigation (ODI) upgraded the investigation to an Engineering Analysis (EA00-023) to determine whether Firestone's recall covered all the defective tires.[2]
Ford and Firestone both issued root cause analyses to NHTSA.[2] Firestone argued that vehicle weight, tire design, low recommended inflation pressure, and lower tire adhesion for tires manufactured at the Decatur, IL factory contributed to the tire failures. Ford argued that the tire design led to higher operating temperatures compared to similar tires manufactured by Goodyear and that differences in manufacturing at Decatur led to weaker tires that were more prone to failure. Ford also argued that the size of the wedge, a strip of rubber between the first and second belts, is smaller in Firestone tires than Michelin tires making them weaker than comparable Michelin tires.
Publicly Firestone argued that Ford's recommended 26 psi inflation pressure was too low and should have been 30 psi.
So... maybe running a slightly lower tire pressure "shouldn't matter," but sometimes it most certainly does. Why should we risk it?
Sorry for the long diversion from the main topic, but I couldn't resist.
HTH
Trust your quality tire gauge.
I have a very accurate tire pressure gauge (Intercomp) and two sets of tires with TPMS. The first set is stock OEM wheels and tires with the original TPMS that came with the vehicle which show on the display within 1psi of my gauge pressure. The second set are TRD Rock Warrior wheels with Toyota TPMS installed by a Toyota dealer which consistently show on the display 2psi lower than my gauge pressure. Point being, the display is not always correct.
So... set RCTIP using your gauge and then reset TPMS even if the display shows a different value.
HTH
I'll qualify and say @gaijin 's recommendations are on point and take a safe stance on the matter. Regardless of modifications, use, driving style, etc.
However, I also apply a healthy dose of informed liberties and agree with @bloc. There's a balance of factors that it's not only about load ratings. If that were the case, why are we seeing the heavier LX derived pressures some 4-5 PSI lower than the LC? Those lower derived pressures are absolutely safe for the LC as well across its full performance envelop. And then you figure there's likely a good safe pressure margin below that yet again for variability.
Absolute PSI precision is really not the goal here. There's various factors of temperatures, tools, absolute vs relative pressure, etc. Engineers weigh these factors and provide recommendations that are guidelines with margin to account for these things. If you consider that the average vehicle on the road also doesn't get their tires checked for what may be huge amounts of time for those lesser mechanically inclined or older beater vehicles, the world is systemically under-inflating their tires. Yet the world goes on. The Firestone/Ford tire situation never had enough safety margin in their design in the first place to be on the road.
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“The Firestone/Ford tire situation never had enough safety margin in their design in the first place to be on the road.”
IIRC, according to an article I read back then, the Explorer, with 5 adults, could carry another 120 pounds or so of additional cargo before reaching its maximum loading capacity. The LC at the time? Another 500+ pounds. To me, that spoke volumes.
IIRC, according to an article I read back then, the Explorer, with 5 adults, could carry another 120 pounds or so of additional cargo before reaching its maximum loading capacity. The LC at the time? Another 500+ pounds. To me, that spoke volumes.
do we know what year this was implemented? I can ask the tire shop but won’t be back for a 5 tire rotation for another month or so.
And yet you have been recommending to everyone a tire inflation pressure 6 psi BELOW what Toyota recommends for their own factory accessory Rock Warrior/BFG combo.
And yet you have been recommending to everyone a tire inflation pressure 6 psi BELOW what Toyota recommends for their own factory accessory Rock Warrior/BFG combo.
Oh, really? Check out page 5: Toyota 17" TRD Alloy Wheel Poop Sheet (Original)
Then we had a lengthy discussion about this, where I presented a pretty complete summary explanation here: Why Toyota now recommends 46psi instead of the correct 40 psi
Then, you appeared to agree with this summary: Agreement consent
So... why now, almost 4 years later, are you picking at this old scab again?
Did you forget?
Do you have new data?
HTH
sorry I couldn't resist. But, yes really, what you posted there is from 2008, and is the original PSI recommendation of 40. They later revised it to 46. I posted a pic of that Toyota sticker showing 46 PSI. I had originally thought what you said made sense, but then realized you were making assumptions on why they revised it to 46. I decided to let it go. But my point in this latest comment is that they now recommend 46 while you say it should be 40. You assume you know why they say 46, but you don't know.
PSI recommendations aren't made solely based on weight loads and tire types. The type of vehicle, weight distribution, handling characteristics, etc... are all factored in. These things change the stresses put on a tire and necessitate alterations to a PSI based solely on weight.
This is what I think you fail to take into account when you do the little load table conversion. But that's just my opinion. Its cool.
But my point in this latest comment is that they now recommend 46 while you say it should be 40. You assume you know why they say 46, but you don't know.
PSI recommendations aren't made solely based on weight loads and tire types. The type of vehicle, weight distribution, handling characteristics, etc... are all factored in. These things change the stresses put on a tire and necessitate alterations to a PSI based solely on weight.
This is what I think you fail to take into account when you do the little load table conversion. But that's just my opinion. Its cool.
You really missed the point, but that's just my opinion - all cool.