I have a 2002 Dakota Sport 4x4 4.7L and am trying to replace the radiator. The problem I am having is the top trans cooler line won't thread into the new radiator. This is the second new radiator that I have tried to thread it into. It threads into the original radiator fine but won't thread into the new one. Has anyone ran into this problem before? Were there more than one thread pitch used on these radiator fittings?

 

I would hope there's not multiple pitches. I've replaced a couple 4.7l radiators and they fit fine.
You could double tripple check the part number of your radiator and make sure it matches your truck.
Or get a handful of different pitch or size nuts and bolts and experiment by fitting them into the radiators and flare nut to see if it really is different. That sounds kind of silly but it's just an idea haha.
If it is a different pitch for some reason you could put on a new flare nut or get some kind of adapter worse case scenario.

 

Since the ATF cooler portion is isolated from the rest of the radiator, you could just leave the radiator lines open and hook up a larger external cooler instead. They sell them all over the place... B&M comes to mind. This is the OEM cooler that came with the tow package on my 4.7L. Not sure if your lines will connect to it, but it's a pretty large unit and maybe you could find one at the junkyard. You'd solve your current problem and get better cooling as a plus. This and draining the tranny every 25K, is probably why my tranny is still rock solid at > 300K.