Had mechanic replace radiator. When I got car home took notice that there were reddish oil spots beneath the car right under the radiator. Checked transmission fluid it was very low. Took car back he said trainy coolant lines at bottom of radiator had to be tightened. When I picked car up, same thing happened, but not as bad. Took back and he tightened them a litte more, and one of them still leaks. He said can't tighten them anymore or the fitting could be damaged, but offered no info on what can be done?
What has to be done to stop this? Thank for any help? Found Problem. The transmission coolant line which is metal was split. Had to replace.

 

The way to stop the leak depends on what is leaking and why. I don't have that information so I can't answer your question. Can you take a picture or accurately describe exactly what is leaking?