The number on the door sticker is the
minimum pressure required to support the maximum payload. Nothing more. A tire isn't going to explode from pressure unless you exceed the maximum pressure imprinted on the tire (not the truck) by a factor of at least 2X and probably more like 3X (which gets you into the 150 PSI range or something utterly stupid).
As long as you watch the wear patterns you can safely run much higher pressures.
I run 40 PSI and there's somebody here who mentioned he's run 50 PSI for years.
Higher pressure reduces rolling resistance which will give you better mileage. However, it can also cause the tire to bow slightly, reducing wet traction. If you see excessive wear in the center, your pressure is definitely too high. This is mitigated somewhat by tire design. LT tires are stiffer overall and resist that bowing at higher pressures fairly well, whereas performance tires are more significantly affected by loss of wet traction since they tend to have sophisticating siping patterns in the tread to help throw off water.
Lower pressure is just bad, period, except in specialized temporary scenarios like off-roading. Excessive edge wear is a sure sign of pressures being too low.
And finally, living in Florida, I have no idea how pressure relates to snow and/or snow tires. Thankfully.
