have a look at this
Load & Inflation Tables | Michelin Truck
really should use the similar reference form your tire manufacturer....but I have been told by someone at Yokohama these are standards and all tire manufacturers use the same data (based on the tire size)
My suggestion...run the max pressure on your door post until you get weights. Do it ASAP, then adjust accordingly. The thing will drive so much better once you get the pressures set by actual weight