Coolant spray/leak

Popped the hood to replace the air filter today and saw coolant sprayed all over the driver side and some on the passenger side. I thought it was the water pump since I have 120K miles but did not see any leaks there.

After looking closer at the spray direction, I saw that it was coming from one of the coolant lines on the oil cooler. I turned the truck off and saw a few drips starting to come out of the connection. Bingo. The line itself looked fine .. no cracks or splits. About a week ago, I did loosen that clamp to get some access when I was changing my valve cover gaskets. I guess that I didn't get the clamp back on securely enough. Its weird that it took a few days to spray. I've was under the hood a couple days ago and there was no spray.

Other than a bad hose or clamp, is there any other reason that coolant would spray from there? I went ahead and pushed the hose on tighter and made sure the clamp was on well. I did not see anymore drips after that.