Actually, It is NOT necessary to disconnect either the transmission or power steering coolant lines on the 5.9 L engine in order to replace the radiator; I've just completed the job. Both the transmission and power steering coolant coils are mounted on the exterior of the radiator. It is a simple process to use twine to temporarily suspend the coils from the grille framework, remove the four mounting bolts, easily disconnect the tranny lines brackets, and remove the radiator without opening either of the coolant lines. Reinstallation of the radiator and attachment of the external coils is just as easy.