Your truck could do it....but I wouldnt. The issue is going to be your manufacturers payload capacity of the weight on your truck. A goosneck or fiver adds substantial amounts of weight to the towing vehicle.Your combined weight will probably be over what the manufacturer states (as Marty mentioned) and your manufactures GVRW will almost certainly be over,unless you figure out a way to remove unneeded stuff from your truck( extra unneeded seats,a single battery , no spare,no carpet,no radio,five gallon fuel tank,no truck box,no passengers,no tailgate,no pickup truck bed...etc.
Look at it this way....if the trailer combo weighs 15k and you have 20 percent of that on the gooseneck....thats 3000 added payload . Thats over for a 2007 psd .(which is what i am most familiar with)
If you are cruising along and some retard decides to pull in front of you...even if he is dead wrong and gets run over...the truck that is OVERWEIGHT will be wrong also. The state will prosecute for manslaughter,the insurance company will abandon you (there is a clause in my policy about manufaturers intended use) and then you will then be sued in civil court. If part of your trip involves California,and they see a single rear wheel axle and if you have a triple axle trailer (pretty hard to do 15 k without it), you will be "easy pickins" for CHP (I have read on glamisdunes.org? that they will weigh you and shut you down on the spot.)
I hope ONLY that I have given you something to check out thoroughly for yourself.
Multi state travel on any vehicle,towed or towee over 10000 is also becoming a state to state issue. Today I purchased a new Bri-Mar dump trailer. It could have easily been rated for 10,400 i believe.Instead it is Derated at 9990. I asked the salesguy why? He replied more and more trailer manufacturers are doing this ,as some states are reclassifying what is automattically a commercial vehicle......and what is not a commercial vehicle.
If i were to guess what is coming "down the road" , I suspect, in the future,all vehicles RATED over 10k will have to pull into weigh stations. Purely a guess and I hope I am wrong. (I keep in mind tho , the highways are governed by insurance companies,first and foremost.)
(My opinion , I do not claim it to be humble

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