From my experience this is not just a simple question.
If you are in a lot of sand then you want to go as low as possible without the tire spinning! Got away with as low 10 psi. <img src="/forums/images/graemlins/smile.gif" alt="" /> (When my front dif failed) I was limited to the back dif with a long way (300km) from the nearest garage! <img src="/forums/images/graemlins/scared.gif" alt="" /> But ground clearance suffer. I also blew two tires (Michelin) under load at 1.4psi on tar without exceeding 80km/ph while I was aiming for the nearest filling station. <img src="/forums/images/graemlins/shiner.gif" alt="" /> Not the manufacturers fault but the tire just got to hot since it was not pumped high enough, very hot day and hot tar, high load and eventually laminated. Most people like 14 here to start with as long as you can pump the tires again and do slow driving in sand.
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