Sorry...another tow vehicle capacity thread

Since I can't un-buy the truck or the camper (especially the camper)...I am trying to find out what the real potential consequences are from continuing to tow with the truck I have. I know it is not the limitations of the engine/transmission because they put the same engine/transmission in the 350s and 450s. Is it the brakes not being able to appropriately stop the vehicle? To make matters worse...I had plan to replace the stock/original fuel tank with a tank that basically doubles the capacity...so I don't have to stop every 250 miles for fuel. Doing this would add another 180 lbs. on top of the weight I detailed above.

Load the fifth wheel up for camping, water, propane, batteries, etc. Then go to the scales. That will give you a realistic number including pin weight and hitch weight. Then take it from there. Being a little over gross for the truck is an issue; but being over the tire, wheel or axle ratings is a big deal. Sometimes there are things that you can do to carry the weight better like larger diameter tires and rims, more springs in the pack, etc. It won't make your gross weight number any better but it can carry the load better. Or, you can always look for a good used one ton, perhaps dually, and sleep perfectly well each night knowing you are under every possible rating and gross weight. When the wife wants a bigger fifth wheel the truck will be ready for it, too.