Cadillac CTS First Generation Forum - 2003 - 2007 Discussion, Radiator fitting leak? Maybe? in Cadillac CTS Coupe, Sport Sedan and Sport Wagon Forums; I took the route of removing the lines from the fittings with the "banjo" type fitting removal tool. Unless you ...
I took the route of removing the lines from the fittings with the "banjo" type fitting removal tool. Unless you have the GM tool, you have to file down the aftermarket one as it's too thick to fit between the line and the fitting in the radiator. I think it would be a lot easier to just cut the lines and either plug the stubs with JB Weld or similar epoxy. Then double clamp the new lines to the external cooler on the metal lines from the xmsn.
I did way more work than necessary and it took 2-3 hrs. Separate bracket for the cooler, etc. It really shouldn't take long and I've had mine on for over 12K mi. and my Xmsn Life has gone from 86% to 84%, plus "Peace of mind"
My GM manual shows the bottom line that exits the xmsn case is the feed line and the return line from the cooler is the top line that enters the case. I don't remember which one it is on the radiator, but just follow them from the case and you'll have the routing. I only lost about 2/3 cup of fluid with the cooler switch over. But I was ready to put the hoses on as soon as I got them out. Good luck.
Just jacked up and followed the lines. Looks like the return line is shown in the top pic and the feed line is the blurry fitting in the second pic. For people in this situation, the top line at the trans becomes the bottom line in the harness as it routes with the other line, past the oil plug and then to the lines.