4x4
I have done that pass at least twice in a stock 4x4 suv.
If two wheel drive, do you have a locking rear diff and aggressive tires.
Chuck Wells puts out great books on 4x4 ing in CO and UT.
He shows some roads that a two wheel drive could do but
I would not recommend Medano pass in a two wheel drive unless
you have what is mentioned above and high ground clearance . That may get you thru the forest part of the trail but the section of the trail actually in the Great Sand Dunes NP is deep sand
and they advise to air down to 15 psi and in the park is a free place to refill tires. That sand may stop even a good set-up two wheel drive truck, maybe a baja type vw beetle could make it thru the sand section. Also, some trails in the state with no obstacles, still have really steep sections where you need the low range of the transfer case for going up and then going down sections without burning up your brakes. The weather should be good that time of year as that is in the southern part of the state.
