A few days ago after driving the Chief to work, I noticed a decent little puddle underneath it when I came back out to it at lunch. Turned out to be coolant. Opened the hood and looked around. Only place I could see coolant was around the cap area and on the little shelf that runs around the bottom of the top tank, where coolant might stand in place if it was leaking from above.
So I thought maybe it might be the overflow tube leaking a bit. Came home that night, removed the clip off the tube on the overflow nipple, inspected and slid the tube on a little further, reinstalled retaining clip. Seems ok, doesn't move when twisted etc. Opened up the radiator cap. She is full, all the way up to the overflow tube.
Drove to work yesterday, no issues. Came back out, no leaks. Drove home, no leaks I could see when I got home. Woke up this morning and went out there, small puddle again (but a little less). Opened up the hood and checked things out. Noticed a little coolant dripping off the underside of the fan shroud, onto the fan, onto the transmission cooler line, onto the ground. Really not much though. Opened the radiator back up, still full to the overflow tube.
Any thoughts on what might be causing it to leak after shutting down/overnight? Only thing I can think is maybe the cap is leaking a bit with the pressure? It's a fairly new standard 16lb cap (no release lever).
I don't think it is leaking while driving/running, but I may try to get it up to temp today and see if I can see anything leaking. Maybe drive around a bit and come back and monitor.
Any thoughts?