When I want to build a good road I put down a base of 1-3 rock and top with crusher run. If the ground is already pretty solid I just dump crusher run or clean 1 down.
Alright, the consensus so far seems to be a load of large gravel, the existing couple of inches was probably 3/4 - 1" range with a bit more we added on top some years ago. You can't tell because so much just mashed in.. Under that the soil is mostly clay, for whatever that is worth. I'm going to look at leveling the area by filing in the ruts then dropping some 3" gravel on top. Add a layer of finer gravel on top of that. I have seen some ads for road millings and I've been impressed where the road crew used that for the new culvert installed a couple of years ago. That stuff packed in great.
I'm hoping about 4" total will do it, not opposed to spending a bit more but I'm guessing this 20x20' area can all be done for $400-600 total. Still wondering if a fabric would be good to lay down before the load of big gravel.
Thanks guys. Still interested if someone else pipes up with experience but I think PandD spoke with a perfect example, hard to beat a school bus for comparison. How thick did you pour on the 3" gravel?