We just did this with our 27’ trailer and will not repeat the experience. One of the rangers told us a 30’ rig got stuck and closed the road for 3 hours and we can see why. The turns are really tight so unless you’re coming at a quiet time of season and day and are really skilled, it is best to take the longer but stricter route from the west.

2 or 3 180 degree switchbacks but with on oncoming traffic you can do it.

Fron Oneida, the is a very steep switchback hairpin. We were extremely careful with our 25ft Airstream. For your rug, I'd prefer the approach from the west.

I haven’t driven a rig that size, but I would probably take the Park Service’s advice to go in from the west via Jamestown. And as others have said, bring what you need for the full duration of your stay. It’s a long way to supplies and fuel.

If it were me driving, I would find another route in. Coming from Oneida there are a few switchbacks on the road going down to the river and back up the other side on the way. But that’s me pulling a teardrop camper that’s 14’. I have seen some larger RV’s and trailers in the campground but don’t know which direction they came in.

Quite honestly, I have no experience with that length. My neighbor had a crew cab and towed 30ft. There were bigger than me in my f250 crew cab with 8ft bed and 22ft trailer, but I found it steep and very curvy. If you venture in, you probably want to ensure you’re stocked up so you don’t repeat the drive unnecessarily