The road is maybe too bumpy for very big RVs without 4x4. For normal cars or big vans with normal ground clearance it is doable. 
If it rains a lot I can imagine that it gets really hard to get up the road without snow chains/4x4.

I was here some days and we saw a lot of tents, some motorcycles, cars, Vans with roof tent and a bigger Van, size like a big Mercedes sprinter.