I buried some spaced 2x 6's on edge that the FW sits on because sitting in the frozen mud has got to be hard on the rubber.
Air can kind of move around the tires and they are off the dirt and out of the mud.
I suggest what ever you use can hold up under the weight of the trailer plus the ice and snow accumulation.
2016 F350 6.7L LB CC Reese 28K 2014 Chaparral Lite 266sab
"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety." 2014 19 days camping 2015 17 days camping201620 days camping