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Old 09-21-2018, 09:39 AM   #31
Tireman9
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Safety Warning

It is one thing to need to add 5% to 10% of the pressure needed to "top-off" your tires. If however you have lost significant amount of air (20% or more ) and had been driving on the tire before discovering it there might be damage to the tire structure which could result in an explosive rupture when re-inflating.
This is especially true for steel body tires. A tire shop safety cage is the ONLY way a steel body tire should be inflated if the tire was ever run with low air.
https://www.caba.biz/Portals/9/Zippe...ll%20Chart.pdf
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Old 09-21-2018, 09:41 AM   #32
Tireman9
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110 psi tires OE?

One question. Did your 110 psi tires come OE on your trailer or did you "upgrade" your tires?
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Old 09-21-2018, 04:30 PM   #33
madmaxmutt
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Quote:
Originally Posted by Tireman9 View Post
It is one thing to need to add 5% to 10% of the pressure needed to "top-off" your tires. If however you have lost significant amount of air (20% or more ) and had been driving on the tire before discovering it there might be damage to the tire structure which could result in an explosive rupture when re-inflating.
This is especially true for steel body tires. A tire shop safety cage is the ONLY way a steel body tire should be inflated if the tire was ever run with low air.
https://www.caba.biz/Portals/9/Zippe...ll%20Chart.pdf
Quote:
Originally Posted by Tireman9 View Post
When a tire loses 20% of the required pressure it is considered "Flat" by the tire industry and should NOT be driven on. While you might be able to travel down the road at a reduced speed you would most likely be doing permanent damage to the tire structure which may come back to bite you weeks or months later when the tire suffers a catastrophic failure.

How low a pressure obviously has an impact on how much damage is being done.


You also need to remember that the companion tire has to "pick-up" part of the load so you could be doing damage to that tire too.
I get the point and passion, but are you only talking about trailer tires? I would just pump it up on the side of the road and drive it. I am pretty sure 90% (Dilbert estimate) of people would not replace the tire because it went "flat" at some odd percentage of full inflation. Which, BTW would only be 6 lbs low, on my Subaru by your 20% number (if this is all tires). If I did decide to replace it, I certainly wouldn't even replace it until I got back home. To me it sounds like an anti-lawsuit nanny state answer, versus a common sense recomendation.
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Old 09-21-2018, 04:57 PM   #34
bob91yj
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If a tire goes low and there is ANY road wear on the sidewall REPLACE it.

This happened to ME...tire went flat/rolled off the bead of the wheel on my car hauler while my off highway Jeep was on it. I put the spare on, took the flat in to Discount Tire, the 18 year old expert there examined the tire, said there was nothing wrong with the tire, remounted it and aired it up for me. I threw it in the back of my Jeep Cherokee, I made it about half way home and the tire EXPLODED...scared the bejeezus out of me.
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Old 09-21-2018, 05:12 PM   #35
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Understand, but what you described is far from 20% under-inflation.
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Old 09-21-2018, 06:35 PM   #36
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Originally Posted by madmaxmutt View Post
I get the point and passion, but are you only talking about trailer tires? I would just pump it up on the side of the road and drive it. I am pretty sure 90% (Dilbert estimate) of people would not replace the tire because it went "flat" at some odd percentage of full inflation. Which, BTW would only be 6 lbs low, on my Subaru by your 20% number (if this is all tires). If I did decide to replace it, I certainly wouldn't even replace it until I got back home. To me it sounds like an anti-lawsuit nanny state answer, versus a common sense recomendation.

The 20% is an often stated number. This applies to all tires.


The average user is not qualified or equipped to properly and completely inspect a tire that has been run when low on air and make an informed opinion on the long-term durability of the subject tire. The 20% figure is the arbitrary level of underinflation where years of experience indicate that the tire has probably been damaged enough to result is a significantly shorter life ending a probable structural failure.
Obviously, some tires can be run at a lower level and not fail while other tires may fail even if the inflation had not dropped to the 80% figure. What was needed is a guideline. What hasn't been discussed on how far the tire was run underinflated. Before the introduction of TPMS some tires might be run hundreds or possibly thousands of miles underinflated. A better answer might be a chart of miles vs underinflation but that requires a lot more data and also requires that a TPMS be used and followed.



The concern is not just based on the possible lawsuit but on the possibility of personal injury to others.


Cars are a poor example as many have significantly larger reserve load margin than almost all RVs with many RVs having negative reserve margin so in the RV the 20% may be too conservative and a loss of 10 to 15% might be more appropriate.
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Old 09-21-2018, 07:07 PM   #37
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The concern is not just based on the possible lawsuit but on the possibility of personal injury to others.
From a corporate perspective, that is the definition of concern of a possible lawsuit.
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Old 09-23-2018, 02:53 PM   #38
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Originally Posted by Tireman9 View Post
One question. Did your 110 psi tires come OE on your trailer or did you "upgrade" your tires?


Load range G 110 PSI tires are standard on my Alpine.
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Old 09-23-2018, 04:48 PM   #39
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For compressors, volume CFM is as important as PSI. I have a compressor that will pump 275 PSI, it will fill a car tire in about three days. CFM is important, I don't have tires that require 100PSI (except my bicycles) for me 125PSI is enough.
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