I don't mind voiding my frame warranty, already have, kind of, but as many hitches as I've built and installed on RV frames, I still don't think I'd put that much weight back there. We used to double tow a lot, but even the tongue load of the boat wasn't near that. Sure, it could be done, but I probably wouldn't, especially on a Lippert I-beam frame. That's a lot of weight hanging off the back end.
John and Rebecca Dickson
Emma-13 / Little John-10 / Iva-7
2013 Ford F-350 Lariat FX4, CC LB PSD, DRW
2015 Jayco Jay Flight 28BHBE (#8)