I tow with the max psi listed on the tire regardless of brand. On my F-250 that means 75 lbs on my E rated tires. I expect yours are either C or D rated which run a considerable less psi, but if I were you, I'd still run the max psi when towing whatever that is.
2008 F-250 4X4 Lariat V-10
2002 Airstream Classic 30' w/SO #2074
2007 Kubota 900 RTV
1996 Ford Bronco
2007 Lincoln LT