I have a leak on the drivers side on the frame rail where the tow hooks are. I have looked but can't see any visible wet spots on the rad or hoses. I am assuming it is leaking between the rad and the plastic tanks has anyone else had this and was it the rad or what?

 

Saw it before.
Can be temperature sensitive.
As pressure builds and begins to force coolant out, heat builds and expands the leak area, then it seals.
You need to look at it from a cold start to fully hot, then you might see where it is.