I get more benefit from putting an extra 200 lbs. of weight in the bed when not towing than from deflating the tires. I ran with the tires for 5k miles based on the load and the tire manufacturer's chart and I saw that if I continued with the lower air pressures I was going to lose about 20% of the tire life.
Now I run with the tires at the PSI shown in the plate on the door frame and all is well in terms of handling and tire wear. It is a 3/4 ton truck and for a smooth ride as a priority I would have stuck with Toyota 1/2 ton mini trucks with their independent front suspension. No way to get a car like ride with a solid front axle.