Where we live , we have pot holes and speed humps to contend with on a daily basis. 4 wheels and good ground clearance help.
They have sand dunes, so raise the front axle to attack a Dune, and raise the second axle to break over a sand dune. Simples:thumb2
Now you can imagine how useful this arrangement is, as long as all 6 wheels are driven.:thumb2:thumb2