I just made it up here in my promaster van. It's very steep in spots, not a ground clearance issue, but I don't think I would try it if it was muddy.

I have driven this entire road in winter in a Subaru Outback. There is occasional snow on this ridgeline and it was both slushy and muddy from a recent 4-6 inches. I had no issues, but I did have a new set of winter tires on the vehicle, and I am sure that helped.