Good chance your tranny has a thermostat.Look through the pass side of the grill,if you see an aluminium block with roughly 3/8" diameter hard lines running to it,that'll be the trannies thermostat.There's kits now i think to bypass it,but i bypassed it on my old 13 years ago by just cutting the ends off the hard lines and flairing them slightly and then used tranny cooler hose to tie them back together.The 13's were the first year to get the thermal management system which included the tranny thermostat. Good chance your 2013 4.7 will have the thermostat as my old 2013 4.7 had it,and it kept the tranny at roughly 185 .Go look through the upper pass side of your grill for that aluminium block,if there,remove it