Looking at a set of 560 60 22.5 for a 14t grain trailer, each tyre will be carrying 4ton At a max of 40kph. mainly over a distance of 4 miles with plenty of slow bits and stopping at junctions. When looking at different manufacturers web sites it say between 30 and 35psi. When talking to a couple of tyre suppliers they recommended 50 and 60 psi. Would be looking at a vredestein or ceat brand. What pressure do others run in similar tyres?