Weighing your RV is not most people's idea of a good time, but it is the only accurate way to determine the proper tire pressure.
It's best to use your tire mfr's tables, but for those that have Michelin, here they are:
https://www.michelinrvtires.com/refe...tion-tables/#/
You can see that, as mentioned above, 61 psi is more than enough. It is good for up to about 4,400 lbs on the front and 8,000 lbs on the rear. 12,400 lbs. That's almost 1,400 lbs over the GVWR, and even over the combined GAWR.
I have no doubt that there are V/Ns on the road that weigh close to that, but most owners stick close to the GVWR of 11,030 lbs or below.
11,000 lbs evenly distributed is about 3,670 lbs up front, and 7,330 rear.
From the chart we can see that 50 psi up front is more than enough for 3,670 lbs, and 55 psi is plenty in the rear.
Needless to say, those pressures are for that example only.
Most people are aware that under-inflation can lead to overheating and in extreme cases, a blow-out.
Unfortunately they often jump to the conclusion that "more [pressure] is better". There are some people who take that to extremes and run 80 psi, because that is the maximum the tire can safely hold.
What isn't as widely known is that over-inflation has its own set of serious issues. WGO, Michelin, Dodge, MB, and others all warn about over-inflation. Some of the problems are:
1) A harsher ride
2) Longer emergency braking distance due to less rubber on the road
3) Accelerated wear in the center of the tread
4) Worse emergency handling
5) More pronounced tramlining
6) Increased chance of punctures
7) Increased chance of a blowout from hard impact
The WGO View manual advises owners to weigh their rig to set tire pressure and to avoid over-inflation.
Almost all truck stops have scales. Cost is about $10.
If you live in a rural area, grain elevators and brickyards, etc, have scales and will often let you weigh for free.