So, you'r esaying that when fluid level is low (cool tranny), the things works fine. When the fluid level is higher (warmed up), the thing acts up? And all the while it has a leak that you suspect. Why would it act normal with lower fluid levels and do dumb stuff when the levels rise? Go ahead with the testing because everybody needs to find the bugs causing the problem. It seems weird that synthetic fluid reacts to normal thermokinetic situations as regular mineral based fluid and acts weird like this.