What does "MAX" psi on tires mean?

Tireman9

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There seems to be a lot of confusion about the "MAX PSI" number on the tire sidewall. That PSI number IS NOT the highest pressure a tire can tolerate. Undamaged tires do not "Explode" if you exceed that psi number.
This may help. Read the words so you understand what the "MAX PRESS" is referring to. The "AT" is an important part of the statement. Some tires may not have the word "at" in the statement.

The "Max psi" is the pressure required to support the "Max Load" which is also stated on the tire sidewall.

We tire engineers test our designs at well above the pressure your tires would get to under normal circumstances.
Tire pressure only increases by about 2% for each increase in Ambient temperature of 10°F , so even going up by 90°F or 100°F you should only see a pressure increase of 45 to 50 psi. If you have weighed your RV and consulted the industry tables on Load & Inflation and always inflate your tires to the PSI indicated in the tables for YOUR load, you will probably only see a pressure increase of 20 to 25%. If your TPMS is reporting a greater increase, you need to confirm your load and your cold inflation pressure and your travel speed which in an RV should never exceed 75 mph.


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Related note: I usually recommend that people add 5% to the Minimum inflation found in the tables, to lower the probability of driving while the tires are underinflated.
 
Thanks for the info, very helpful. Is there an easy reference for “ industry tables on Load & Inflation” you can post. Is this tire specific?
 

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