New 30ft Trailer Towing Experience

Hi guys! Sorry for the long absence. Got very busy with work and family. Finally pulled the trigger in May on a Grand Design Imagine 2150RB. So far, have only had a chance to tow it home, about 45 miles, practice turning and backing in a big empty parking lot, and tow it to a storage location. We plan to go camping somewhere not too far away after our daughter's wedding next week! I had a question I have been unable to get a answer for from anyone: how do I know how much pressure to put in the TV tires when the RV is hooked up and in tow? Normal recommended pressure on the Sequoia door post is 33 psi. Max pressure on the tire sidewall is 44 psi at full load. Appreciate any insight. Called Michelin and they were no help. Ditto with a tire shop here that sells my tires. Thoughts? Thanks!