The entrance from Hwy 163 does have a small wash to cross and then up hill for just a short way, but accessible by any rig with no problems. I crossed it with a 40 foot fifth wheel. Most of the sites were large enough for my rig and some of them were fairly level, may need a block or two depending on the angle you want to park at but nothing major. I managed with no block needed at all,

Most sites should fit your rig with no issues. The last site I used was very flat and could have held 2-3 trailers your size. There are quite a few sites, i would try to get there by late afternoon. You will have more options for sites, and it is incredibly dark at night. Beautiful place.

Yes - there are all kinds of different sized campsites. Some are small and some can hold semi trucks haha. I definitely recommend entering the loop from the 163 and not from the 261. There will be a steep slope from the 163 on entering but way easier from that point on than entering from the 261. I'd also recommend dropping your trailer at a large spot you are comfortable with and then driving the rest of the loop to see if you find a better spot that you are comfortable taking your trailer the rest of the way. This loop through Valley of the Gods is UNBELIEVABLE! You'll want to drive it anyways- plus you'll find some really incredible camping spots that you may have no issue getting to. It has to be one of the best dispersed areas in the USA. I have a 16ft trailer. Rod

Yes, depending on what parts you choose to camp. There is a shallow wash you must cross just off the main road, but after that its smooth driving.

Some are. As you drive the loop, you will see many pullouts (check out in advance using google maps satellite view) there are quite a few large enough for your trailer. Note the NW corner of the loop has some very tight turns, you may want to avoid that by coming in from the eastern entrance (closest to Bluff)

Yes