Towing off-road trailer in SAND

[INSAYN]

How are you making the determination as to what tire pressure to run. I use chalk with the trailer loaded, make a line across tread, then roll it over a few revolutions and look at chalk line. With my trailer and weight I came up with 17 psi and I have good contact pattern and no wear problems. Do the same with Jeep, and on 35's my street pressure is 25 psi.

Are you referring to highway pressures?

I start with the recommended pressure on the door jam, and adjust from there with either chalk or just a narrow tread wide swipe from a soapy wet towel. It cleans the rubber good enough to see where the tire is contacting the road, or not. A paint pen works too.