Travelnutz,
I like your style, but there is nothing packable about the sand in anutami's pic. I have been on that route. About 2 feet down you will encounter a harder pack than the pic shows, but it will bury you to the frame if your try to drive up grade in the stuff at full pressure. The beach at Fort Stevens, OR is packable: (we were here a couple days ago)



Even then, the drier, softer edge blow sand away from the surf can swallow your rig. We were on the beach trying out all our 'drive on soft stuff' appliances like the front Eaton-Detroit True Trac which kept all wheels pulling, and the widemo rear tires, at full pressure with approaching no sidewall deflection. On real soft sand I needed more pedal to pull through, but it never stopped pulling even with 10,500 pounds of rig. I have driven on dune sand of which you speak and there is no way to keep forward motion without dumping the pressure way down (but not below 20 pounds all around). Ten pounds will walk your tires off the rim on a TC unless you have bead locks. It's all a matter of weight vs. floatation. These two issues are particularly edgy with a hard side truck camper, but it is do able. There are rules: one; never drive uphill in the sand. two: never stop in the softest stuff. If you do come to an unscheduled stop, instantly put it in reverse and try to ease your way back the way you came using what little momentum you have. You have already made a channel to drive in and your sidewall biters will help a little.
How about driving in quicksand? Yep, I've been there but not for a long time and not again. Right down to the frame in 1970, Salt Creek, Canyonlands NP:

jefe