I know this is an older post but, the same thing happened to me,
Now this is a steel pipe and it's solid on each end, if their is a vibration between the radiator and the transmition, something has got to give, so yes mine did crack also,
What I ended up doing was remove the pipe, blaze the fitting back on, the I cut the pipe in two, took 6 inch off the length of the pipi, braze 2 fitting on each end of the cut, then had a small 6 inch hydraulic line made and installed this in between my two halves, and re install, now their a rubber Hydraulic hose in the middle of this steel pipe, this hydraulic hose absorbs the vibration,
I hope I made this clear? If not ask me some questions.
Thnx
I ended up having it brazed. It's working well. The new part comes with a bracket to support the tube halfway between the two points. I haven't added a bracket yet; but plan to do so when it warms up a bit.