Hello. I was just looking over the engine real good and noticed what i believe is the oil cooler line has a dirty oil film on it where it comes ...

Hello. I was just looking over the engine real good and noticed what i believe is the oil cooler line has a dirty oil film on it where it comes out of the radiator and slopes down. The rest of the line is clean but this spot seems to entrap dirt almost as if there is a slow leak. Nothing is visible on the ground. Is this a common issue? Is this even a oil cooler line. I have the afm 5.3. Thank You

Are you sure it is not the transmission cooler line? The new trucks have a quick connector on those where they go into the radiator (and transmission). It may have a seepage from that area. I'd clean it off real good and see how bad of a leak it is. If it's just seepage, I wouldnt worry about it too much. If it is more than just a slight seepsge, you can get the new end with the seal for that connector at any autoparts store and replace the one that is leaking.