I have seen people drive it in a car and even bring in motorhomes (we took the 4x truck). We didn't really encounter what I would consider real rough spots just the normal washboard back road in spots. Along the road are a lot of camping locations and a few lakes so it is a well traveled road. It looked like the west end in the Coconino Forest had been recently graded with road work signs along the way. The east end on the Sitgreaves Forest always seems to be rougher to me but it widens out there so you can drive around the pot holes.
Dave