So I’m replacing a radiator on my 2005 Saab 9-3 auto. I got a used radiator from a 2003 Saab 9-3, and everything fit well. But I started filling radiator and there’s a leak on the lower oil or trans line(whichever Fluid line is on the drivers side radiator). It’s leaking water but I threaded in the oil line nice and tight. Is there supposed to be a gasket for these lines Or lock tite? It’s leaking water because the line is loose(not the threading) I can shake line around inside the radiator. Or do I just need a new radiator, where you don’t have to line up the threading from inside the radiator?