7.3 Blowing trans fluid in tow
 

Truck running fine, replaced injector cups, oil cooler, installed an air dog fuel system ,has a bully dog tuner with four settings, was towing a 6500 lbs camper and pulled in and pouring trans fluid. 7.3 with 221k miles on it, ran tuner on towing mode and didn't notice temp on trans going up, so a little confused. Drove it a few miles few days later without the load and not a leak in site.
Any suggestions?