Der Carrie;
You are new to class A. Before you go anywhere first we need to determine how old the tires are on the rig.
If original they are 10 years old. This is very near the end of their useful life NO MATTER HOW MUCH TREAD is left on the tire. It is a matter of chemical breakdown in the tires causing failure of the tire.
Now as to tire pressure inflating your tires to maximum RATED pressure will not cause bad things to happen to your Motor home. It might increase tread wear somewhat, it might give you a rougher ride but no major problems should happen to your rig. SO you can either become obsessed by your tire weight or you can set it and forget it. THE CHOICE IS YOURS. Both ways work for people. I am a set it and forget it person my tires (new) are at the maximum pressure for the tire.