You seem to have some embedded misunderstanding here....
Have you had the trailer over a scale?
If not, then do it. Use the table on the tire manufacture's site to determine the correct inflation.
The sole reason that the rims and maybe the tires both specify a maximum inflation of 80PSI is that any higher pressure may be dangerous. It is not a suggested inflation.
A tire with a higher than needed load rating will be no issue. This is common these days as manufactures are cutting the number of ranges because improved technology means that tires can now handle higher load so there is no cost reduction for the lower load tires.
Example:
For our coach, a load range D would be safe. But I run only load range E tires for one very good reason. They are more available and the same price as LRE tires.
A gentleman was telling me that his coach (like mine) handled and rode terribly. I drove it, and he was right, it bounced around like a BB in a bathtub. I asked the tire pressure and he told me he had set them to the recommended on the rim or tire.....
When we let all the tires down to where they should have been, the ride and handling were much improved.
Matt
Matt & Mary Colie
A sailor, his bride and their black dogs (one dear dog is waiting for us at the bridge) going to see some dry places that have Geocaches in a coach made the year we married.
