I ran my 32x11.50 BFG MTs at 18 psi and they did great! You can always experiment and air down to match the conditions. When I went the sand was very loose so you would dig down easily. If the sand is more firm, you may not need to air down as much. Since you traditionally run faster in sand, I wouldn't go lower than 15 psi.
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2000 Silver Ice 4x4, SE
ARB, 32" BFG Mud Terrains
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