I'm pretty sure you'll get the standard replies on this one so let's see if I can sum up in one post.
1. Start with PSI stated on driver door placard (Ford's recommended pressure)
2. Increase/decrease pressure in 5 psi increments depending on your preference, load and environmental conditions
3. Perform chalk test to determine over/under inflation
4. Don't exceed max PSI stated on tire sidewall
The Following User Says Thank You to kobayashi maru For This Useful Post:
I had a Tahoe with duratrac e rated tires which wore out prematurely from running what a good year vendor told me should be 35 psi as the door sticker stated. Than I tried running stupid high unloaded which was crap for ride quality. I finally settled at 50-60. My wife's expy now has duratracs too, which I run at 50-60 as well, no issues.