As said before, stated pressures are always cold.

As far as the correct pressure for the load, it is best to use the tire manufacturer's load/inflation tables as a guide. It should be ok to go over the recommended pressure for a given load as long as you don't go over the max for the tire. Don't run less than the recommended pressure for a given load.

Here are a couple of links...
http://www.trucktires.com/us_eng/technical/index.asp

http://www.goodyear.com/rv/tirecare/...iontables.html

Dave