I have always been confused by Ford's CGWRs, in theory GCWR is rated by the drivetrain and not so much about how much weight the truck can haul (the GVWR). This is where we get the F150 that can tow 11,000lbs of trailer - but only tote about 1600 lbs in its bed. On the F250/350 they seem to also take into account the GVWR when computing GVWR - I have seen where the same drivetrain has different CGWR based on the GVWR package. Well, I have searched several Diesel Forums and all of them point to a 20,000 lb max - until 05 when they uped it to 23K and 26K for the Tow Boss package.
07 Chevy 2500HD 6.0L ,6 speed auto, 4x4, Blue Granite Metalic
05 Arctic Fox 22H