I have a trailer, not motorhome. But the best advice I could give is to weigh the front axel and both sides back when loaded and ready to roam. Goodyear suggests tire pressure to give a combination of ride, braking and longevity.
In the past I ran up my tires to max, shook cabinets open and made a mess, even cracked a cabinet. Then I weighed my rig and found that 55 psi was what I needed to carry my load, not 65 PSI on the sidewall. This was due to my purchase of slightly over capacity D tires to replace the C rated tires which were maxed out, Chinese and out of date.
In short, inflate to carry the load, to much or to little will hurt ride, efficiency, tire life and most important, emergency braking.
2017 SLX 195RB
2021 Jeep Grand Cherokee Summit L 5.7L V8
Andersen WDH hitch, Renogy 100 AH Lithium &
200 Watts solar panels from Renogy
Prev. '14 Jeep Grand Cherokee Overland, gas 3.6 V6