It never ceases to amaze me the amazing overconfidence of people towing trailers. Some 5th wheel units are as heavy as 20,000# and very long. The real problem is they are being pulled by essentially a class 3 truck (<12,000# GVWR). The safety systems on a Class 3 truck are not designed to protect passengers in the truck at the truck's GCWR only the GVWR with proper load restraints. I have seen video of accidents where there was a brand new truck and 5er with the truck crushed on its side under the 5er. Not a good situation. I have also seen video where a pickup truck (dually in this case) was flipped up and over just like a toy by the very large heavy 5er. That is the real problem. The 5ers are too heavy and the trucks are two light. The safest rigs I have seen are the Class 5 - 7 medium or heavy-duty trucks hauling the large 5th wheel trailers. Those trucks are wide and heavy enough to handle the weight. It is too bad that Class 3 truck OEMs try to stretch their specifications to reach into the light-medium duty class. In reality, those trucks are not designed to handle that sort of weight, height, and length. Sure, you can tow and stop under ideal conditions which rarely exist on actual roads. Plus add that a lot of drivers go way too fast for conditions in these rigs things can go wrong very quickly.