More power for sand driving

I had a great time lowering the air pressure in my 265's and getting out on the sand dunes this last weekend. My friends v6 jeep would pull me on the hills, many of which I would get to the top, but not quite be able to crest. Any ideas on how to get more power for that extra oomph at the dunes? Or is it a lost cause.
Also if I lower my air in the tires at the dunes is it okay to run a few miles on at the low air pressure on asphalt to get to an air compressor?

 

Probably just better tires with lower pressure. How low you can go with the pressure on ashpalt depends on what kind of tire you have, and how thick the sidewalls are I think. If you post what kind of tires you have people should be able to tell you how low you can safely run them on asphalt.

 

Im running Toyo A/T 265/75-16 when i air down i go to 18psi rear 20psi front and no problems with driving on roads. i once aired down to 7psi in the rear for some mud. i was fine driving on the road from that but don't turn hard or power hard on the road you might pop the tire of the bead.

 

Which dunes were you in??

 

265 A/T's three different types. Those dunes are close to you. The Nellis Dunes out at Apex.