Unfortunately I didn't get to do my planned overnight on Tonga ridge. The road is pretty decent until 4 ish miles to the trailhead, where there are deep ruts in the snow, with the tires driving over ice. It wasn't too difficult going up with awd and road tires, but eventually the car started having trouble getting up, so I decided to turn it around, which is where the problem developed. The ruts on the road are very deep, which makes turning around, especially without snow or AT tires very difficult. I ended up cutting out a path for the tires with my ice axe, but it took about a half hour, and I didn't think I would make the ridge in time. I'll have to come back at some point, but I wasn't able to make it this time. I would recommend this road only for highly capable vehicles and drivers with snow experience. Even then, there will still likely be some road walking tacked on.