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Lowest possible pressure will give you the widest foot print. But it is likely that tire pressure is not your problem...
there has been much said about operating ZTR mowers, most damage is made at turns by operators that Do Not take the time to understand how the machine operates, so they do 'pivot' turns and it naturally burns a spot out where the wheel is standing still... Change the way you turn, do Not turn while any wheel is stationary and you will Never damage the turf... :smile:KennyV