My crew cab long bed (about 22' long) along with my 17' (21' bumper to tip of tongue) can get me into some pretty tight Forest Service campground roads - but I have to be careful due to the length of the truck and the trailer is only 7.5 wide. I would not hesitate taking that combination to a National Park.
My 35' FW - that I would not take to the same Forest Service campground I take my shorter bumper pull. The term "off tracking" is because the FW does not come close to following the same tracks as the pulling vehicle on corners, especially tight corners; whereas the bumper pull tracks pretty closely.
