On my 2009 xD, the auto trans fluid inflow/outflow cooler lines are connected to the bottom of the radiator: one line threaded into the driver's side of the radiator, the other line threaded into the passenger side of the radiator, ie "side by side" . . . . rather than one being above the other (on radiator side tank) as on 1960s/1970s V8 American cars. Does anyone know which is the ATF inflow radiator line, and which is the ATF outflow radiator line? Sure, I could use the messy method of taking one line off & starting the car to see which way the fluid sprays/runs . . . . but I'd sure rather learn by service manual data, etc. I'm going to add an auxiliary auto trans fluid cooler. Perhaps it won't make a great deal of difference whether I insert the external trans fluid cooler "pre" or "post" flow through the radiator cooler, but the greatest cooling would occur "post" or after the radiator ATF cooler outflow. Any guidance sincerely appreciated.