You already have a combo already. Take it to a
a scale to find out where you stand with respect to all your truck's ratings. Looks like current TT has dry weight listed around 5600 pounds, so you will quickly calculate how much extra your family takes as well.
I tend to stick to about 6k dry for half ton recommendations. That tends to be 7k loaded with 900-1000 pounds of TW. A bed full of camping gear or toys and some people in the cab tend to very quickly exceed the 1200-1600 pound of typical half ton payloads. You are considering 7500 or 8000 pounds dry, so 8500 pounds loaded. That would be 1000-1200 pounds of TW. How much rear axle and payload do you have available?
