My dad had a new set of tires put on his flatbed trailer. They are a 7.5 x 16 with a max pressure of 70 psi (7K axles). The tire dealer only wanted to put 60 psi in the tires but Dad thought they should be at full pressure 70 psi. The dealer tried to explain that once the tires heated up they would be a full pressure. Dad and I both think that the dealer is wrong since we have been running the orginal tires at 70 psi since the trailer was new and the sidewall reads maximum cold pressure 70 psi. So are we runnning to much pressure in the tires? Normal loads of 9K - 12K on the trailer.