The 18k B&W Companion that caused bed deflection when towing heavy was designed to be used in a truck that had some strength in the bed. Since its design the bed metal has gotten much thinner. So B&W provided spacers to transfer the load to the cross members. B&W re designed the Companion for the newer truck bed weakness. It now comes as a 20k model.
I towed my 18k RV with my 18k Mobile Suites with zero issues after the spacers were added. I would have zero issue with towing a 20k RV with a 20k Companion based on my personal experience.
My current 25k puck RVK 3600 Companion is in another class!
