Higher pressure will make it a little stiffer, also more harsh, especially if the front has any weight off of it with the trailer hooked up.
60 psi is about right for the front of a diesel with that size tires.
You're just driving on taller sidewalls, that's all. It's not going to be quite as crisp as with shorter sidewalls.
That's why I get a laugh at all the guys here saying bigger rims don't have enough sodewall to be a truck tire. 285 60 20s are basically the same size as you have, but drive better.
Nothing wrong with those tires though.
