What size and load range are they?

My brand new triple axle hertiage trailer came with 235/85R16 Goodyear G614's load range G. They can be inflated to 110 psi. However, my sticker on the trailer says 245/75R16 at 80PSI to carry the load. Every time I look at it I think the same thing that is a lawsuit waiting to happen. With the 235/85R16's I actually need 90psi to carry the load. I haven't taken the wheels apart but I am guessing they are only rated to 80PSI like most of the wheels too. Hard for me to understand that they can be that clueless about proper ratings.

Load range G or H 110 psi. E 80 I just changed all my 16" marathons to 17.5 Load range H. We will see how the tire life does now!

Sometimes it's ok... Goodyear published this Service bulletin recommending 10psi over max on marathons. Like others have stated, run max sidewall pressure, unless you have the tires listed in the link below, then add 10psi.
https://www.tirerack.com/images/tire...plications.pdf

On the trailer, I run 5 lbs. less than the max inflation pressure listed on the TIRE. Tire pressures increase with heat. Even though they list "cold" tire pressures on the tires, I like a little buffer.

I read it different from you.

I can't find the exact pdf I saw a few years ago, but it specifically called out 75 psi on "65 psi" tires. Remember all my tire issues on long highway trips? 75 psi, problem solved.

Slightly related question. When your 3/4 truck is not loaded/ towing can you run lower pressures just to improve the ride?

Yes.

How much would you drop them? Down to 35psi or so, similar to 1/2 ton pressure?

I prefer 45-50psi. You may like something different. Over 50psi I can't stand the ride....which a lot of it is dirt roads and broken pavement. Oh, winter traction suks with a lot of air pressure.