Tire PSI and truck camper question

robertjp wrote:

jadatis wrote:
Your tires are most likely Standard load P-tires, and on those they only give maximum allowed cold pressure.
The maximum load of tire can be carried up to 99m/h AT 35 psi , wich is standard reference-pressure for P-tires SL. So if you drive only below 99m/h you may use the 35 psi.

The space between 35psi and 51 psi is used to highen up the referce-pressure ( further AT-pressure) for higher speed then 99m/h with a system depending on speedcode of tire. Also for alighnment camber angle above 2 degr.

LT tires give on sidewall the AT-pressure , and in earlyer days higher was allowed and even adviced upto 10 psi extra, but nowadays the tiremakers dont allow it anymore, and so the AT-pressure is the maximum allowed cold pressure.

So tiremakers allow for SL P-tires a higher pressure then AT, and if you use it to cover some higher load on tire then maximum load, they cant prove you did it for that higher load then max ,that they dont allow, but mother nature will be happy with it.

To high pressure gives that less deflection of tire, that things go bumping, so to high is not bad for the tire, but bad for your kidneys and teeth-fillings.

OK so now Im confused. Can I up the back to 51 PSI or not? Im not an expert. I was going to but after reading the last post, Im not so sure. Thank you.

A lot of irrelevant info. No need to overthink it. Yes they say 51 psi You can and should put 51 psi in them when hauling a heavy load.
Check out a load v inflation chart for tires, any tires. You'll see the relationship of capacity relating to pressure. But it's not rocket science. You have 2500lb cap tires you're putting at least 2000 lbs on each. You should be in the upper end of the max psi for the best performance for that load.
Some of that above confuses me too........