Regarding towing, with that load you should be using tow/haul button on the dash. It keeps it from engaging overdrive. Also, 96 degrees is pretty hot so you want to take extra precautions, like opening the hood when your not driving to let the heat that has built up out. Also, the amount of gear in the boat and in the Commander, that is, extra weight, use up capacity and add to heat build up. You may have been over capacity. Boat motors are heavy, as is gasoline and any water in the bilge, battery(s) etc.
It is also a good idea to drive like a gramma so to speak when towing heavy loads in that kind of heat to keep from taxing the whole system, more stomping on the gas to pass someone going uphill will build up heat in a hurry.
I'm not saying you did that, but you get the idea about building up heat. It is harder to dissipate heat when it is 96 so you have to drive to accomodate that.
2007 XK Limited, 5.7L Hemi, QDII, Rusty's 2" lift, Spidertrax 1.5 inch wheel spacers, GetLost4x4's front hitch mount for portable winch.GY Duratracs 265/70R17s , Rola Roof Rack, diy built spare tire mount for the roof rack.