I AM looking for the manufacturer's recommendations. My previous post was a brain dump. Here's the short form...
The pressure given on the truck door or on the trailer is the maximum, corresponding to the GAWR and GVWR. Goodyear publishes a chart of recommended tire pressures for various lesser loads for the truck tires and the trailer tires (see
http://www.goodyear.com/rv/pdf/rvbrochure.pdf , also shown on the splash page of this forum). If we had Goodyear tires, then I would just follow the chart - which ARE the manufacturer's recommendations. However, we have General Tires. General does not publish a chart of recommendations, just a bunch of warnings not to over-inflate for the load. I have sent their customer service department a request for recommendations. I'll post their response.