Corky, Also, the tire pressures on the Safety Placard are typical suggested safe tire pressures based on the Gross Vehicle Weight Rating. That's the very highest possible weight specified for your RV model. Because you are likely not at the maximum GVWR, those pressures are not ideal nor are they necessarily correct for your RV as you use it.
You "may" find that if you weigh your RV, fully loaded with fuel, water, all your stuff and all passengers that you can safely lower your tire pressure and get better ride quality and longer life from your tires.
The process involves getting your RV weighed as mentioned above and then using THOSE actual weights you check the tire inflation charts for your exact tires, size, model etc published by your tire's manufacturer. That will give you the best tire pressure to use on each tire on each axle. Most of us add 5 to 10 psi to the rating on the tire company's pressure charts for extra peace of mind.
If you did this you may find that instead of running 120 psi on the front tires that you only need 105 psi. and maybe for the rear instead of 95 psi you only need to run 90 psi.
Finding the correct tire pressure based on your actual loaded RV weight can really improve your ride going down the road.
NOTE: Using the Tire Placard's PSI should be safe and it's obviously easy to follow. So using it is fine - it's just not necessarily the best for both ride and tire longevity.
2017 Winnebago Adventurer 37F
2016 Lincoln MKX Toad