RV Manufacturer versus Tire Company air pressure settings

No, you would weight your rig with it ready for the road including water, groceries, accessories(bikes, and other toys) and people. Get the correct air pressure from the tire manufacturer chart. Add about 5 pounds so account for weight changes due to fresh water, grey and black water.

The right way is to weigh it and then adjust for the amount of weight, hopefully four corner weights. I go 5 psi over the heavier tire on each axle because I'll drive when there is a big cross wind which shifts a fair amount of weight to one side.
Unless you always travel without any water in any tank (which I doubt) then maybe. I weigh mine with full fuel and water plus all our normal stuff on board.

wolfe10 wrote:
NO, the PSI on the GVWR sticker (usually by the driver's area) indicates THE CORRECT/MINIMUM PRESSURE WHEN EACH AXLE IS LOADED TO ITS GAWR.

Hopefully, your actual weights will be well under GAWR and therefore the correct/minimum PSI will be less.

The 70/75 psi levels are from the GVWR sticker. You're saying that if I'm traveling with no water I would actually go lower than the 70/75?

What Brett said.

NO, the PSI on the GVWR sticker (usually by the driver's area) indicates THE CORRECT/MINIMUM PRESSURE WHEN EACH AXLE IS LOADED TO ITS GAWR.

Hopefully, your actual weights will be well under GAWR and therefore the correct/minimum PSI will be less.

Winnebago sets them for a soft ride. Tire mfg lists for maxinum load carrying capacity. If you read the tire sidewall it will say something like.... XXX pounds @ XXX PSI