Read PapPappy's post again. Fill the tires to the max as posted on the sidewall BUT, make sure you also read about the weight capacity of each.
I purchased a brand new Starcraft hybrid a few years back and aired the tires to the max. After a failed tire I noticed that the weight rating of the tires was just a couple of hundred pounds over the actual weight of the trailer. I weighed it at a scale to be sure. Carlisle replaced all 5 of my tires but it took some serious convincing for them to come around.