245/70R19.5 tire Air pressure Loaded and not loaded?

G rated tires are rated at about 4800lbs each with 110psi. At 55psi, each tire is capable of about 2400lbs. Or 4800lbs total tire capacity on the rear of a truck that weighs about 2700lbs total when empty. Nothing wrong with more air pressure. I was looking for softer ride and flat tire tread (with chalk) when empty. Truck was a daily driver at the time.

I run my spare tire with Zero air pressure. No other way to fit on the truck with Superhitch. I have an onboard Air Zenith compressor.