Ford: fx4 towing, tow weight, 5th wheel

Question
My f150 is a 2004 (new style)  I just purchased a 5th wheel that weighs 8500 lbs dry and a load cap. of 3500 lbs
My truck is rated at 9700 lbs max tow weight. I know I cant carry the  trailer max , but I have noticed  each newer year thay have upped the max towing for the same truck as mine. I know we put in about 1000lbs of "stuff" not including water and propain I figger i'm about 500 lbs over Fords max. but the 2007 (same truck) will handel it. can I safely get by this close or is there somthing I need to add to my 300 hp gas rated truck?  Thanks for your time!  Dave

Answer
I am sorry i cannot tell you to haul more then your truck is rated for Dave. But i can tell you it really has more to do with safety more than your horsepower. Government regulates that a vehicle has to be designed to stop in a certain distance with a desired maximum load. the 07 brake system does handle more then the 05s same pads and such but the valving and proportioning valves are metered different. also tires play a big role in load capacity of a vehicle as well as maximum speed and governed speed. I have a 4.2 in my f150 and i can tell you it will outhaul what it is rated for hands down but I know i shouldn't work my truck that hard because of the safety factor I have a  hard time stopping and handling the trailer. Personally i have seen F150s haul extreme amounts of weight and handle nicely, the downside is what happens if something does go wrong? Sorry i could not be anymore help.

Regards

Jim