The 15,500 lbs is going to be a for a stripped down truck and a trailer with a very low tongue weight. Here is the best way to figure out what you can tow. Take your truck to a Cat scale
and weigh it fully loaded with all passengers, pets and gear you intend to routinely have in it when towing plus a full tank of fuel. Put the front axle on the first scale pad and the rear axle on the second scale pad. Bring a broom handle or something like g as the button you need to push is really high up. When they ask for first weigh or reweigh, it is first weigh (if you use the scales to set up wdh you can reweigh for $1-2/time in the next 24 hrs, 1st weigh is usually $9-12). When they ask for truck number tell them private vehicle. If they still need a number give them your favorite number (they get way too many number 1's).
Now take your yellow weight ticket and look at the numbers on it. Take the total scaled truck weight and subtract it from the trucks gcwr to get your adjusted towing capacity. Take the scaled weight and subtract it from the trucks gvwr to get your available payload. Take the rear axle weight and subtract it from the max RAWR.
If you can't get to cat scale, you can look at your tire loading sticker for "all cargo and occupants should weigh less than x lbs". Subtract the weight of everyone and everything that will be in the truck when towing. This will give you a rough available payload estimate to work with.
The loaded weight of the tt needs to be less than your adjusted towing capacity. Your loaded tongue weight needs to be less than your available payload and axle weight ratings (although a properly adjusted wdh will transfer some weight back to the tt and forward to the front axle). Not knowing how heavy you will load your tt, it is safest to do all calculations using the tt gvwr (the most the tt should weigh when loaded). Although that said, you will not likely put over 3000 lbs into that tt, on average people tend to add 1000-1500 lbs to the yellow sticker weight on the tt. Ideal loaded tongue weight is 13-15% of loaded tt weight. CalculAte 13-15% of the gvwr or loaded tt weight (whichever o be you are using) for now to get an idea of whAt tongue weight you will be carrying.
In this case we are looking at a dry weight of 7374 lbs. 7374 + 1500 lbs cargo = 8874 lbs potential loAded weight. 8874 x15%= 1331 lbs tongue weight. If you use tt gvwr of 10700 lbs and a 15% tongue weight then you are looking at a tongue weight of 1605 lbs. Now are these numbers less than your available payload? Also check to see what your hitch is rAted for as some class v hitches are rated to 1500 lbs with wdh and others are rated as high a 2000 lbs. Not sure where ram falls on this spectrum.