What PSI for tires?

JIMNLIN wrote:

cummins2014 wrote:

JIMNLIN wrote:
IMO he doesn't need to read pages of tire jargon
What he will be getting is a broader perspective in answers from a actual tire engineer on this subject with no rude comments.

Not sure what’s rude ,if you are referring to tire jargon , so be it . But with his fifth wheel, GVWR, I’m not sure doing anything but inflating those OE tires to max inflation , and hope for the best , considering there is a good chance they are a cheap ST tire .You might want to elaborate on what more would be gained by reading pages of tire terminology, and still not coming up with max inflation . I’m sure you could condense it to something besides pages of reading .

The rude comments that were made wasn't done by you but was done towards the OP by others.
Your advise to use max sidewall pressures is right on. However Tireman9 blogs goes into tech details why its necessary to do so which the OP may or may not be interested so he or you don't have to read it.

OP if your trailer has 7k or even 8k axles the best on the market for price and long term reliability is the S637 Sailun ST G load range which is a commercial grade all steel ply carcass tire made for the service trailer industry. There a long term tire with a long service life and work great on rv trailers.
The S637 in a ST235/80-16 G at 4080 lbs capacity at 110 psi. Just make sure the wheels can handle the higher pressure needed.