I noticed that the coolant line that runs up to the heater core is leaking right where it goes from rubber to metal. It's the joint next to the idler pulley. I tried to "twist" the line, but it seems tight. It has one of those clamps that you have to use pliers to undo so I can't just snug it up like a hose clamp. Has any had trouble withthis before? Maybe I should just put a good hose clamp on instead. There's miles of coolant lines on these trucks! I hope no more leaks appear.

Well as it turns out it is not the clamp. Where the metal bracket is welded to the line, it cracked on the line and that's where the leak was coming from. I'll have to take it off and weld it up. For now a piece of 5/8" rubber line will do as a bypass.