I have a 2002 Truck and noticed today that the radiator overflow was leaking all over. I thought the worst " head Gasket". What has actually happened is leaving the transmission entering the bottom of the radiator is a line it then exits from the top of the radiator and enters the external transmission cooler and then back to the transmission. Inside the radiator there must be a crack since the transmission fluid is mixing with the radiator fluid. I am somewhat relieved, but also confused as to why they are using the radiator in the first place? I want to disconnect and plug the lines to the radiator and have the lines go direct to the cooler and back. I do not know if I can do that or not?