The highes- low ranger gear is the best when in sand,because you don't want you tires spinning when you start to take off from a dead stop are your tires will go down into the sand quick,that's why you don't want to put it in the lowest gear either or your tires will spin to much ,which would cause you to go down and may cause you to spin a axle.If you used the high range then it would put all the torque to your back tires and wouldn't have any use of your front tires.