My truck does great with the stock Rebel settings of 55F/45R, your crewcab should have a similar weight bias to use those settings. just got them rotated & balanced at 5,000 and the tire guy said no issues with abnormal wear patterns, cupping, etc.
Would I run them lower? Maybe, just to see how they felt. However I don't want to stare at a orange low air pressure light and a warning to pump up my tires every time I drive my truck.
I can buy a tuner to change that, but I honestly think they run fine on the street with the OEM pressures, everyone who rides with me says my truck is so comfortable. For off-road, I typically run 25 psi all around, sometimes down to 20 psi in more sandy situations.