Found this on another site. I like all this technical lingo. Only thing about it is that I have tried this and it hasn't fixed my issue:
"I have a 2010 with the 6.4 and it didnt start ticking until the first oil change. I ignored it after reading the TSB that Ford released stating it was nothing to worry about and was related to tolerances in the bottom end (rods and mains). However I noticed it went away after a few thousand miles into the second oil change. So the third time around I carefully watched the amount of oil on the dipstick when the 15 qts were added, and found something shocking. This engine is over full if it has 15 qts of oil, even though thats what Ford and INternationsal says it holds. Adjust your oil level to where you show about 1/8th of an inch below the top full mark, and it will stop the ticking. When the oil is cold its thicker and tends to string out more like honey and sticks to the block and rods, but when it heats up it gets more like water and drains quickly back into the pan or sump. What you are hearing are the counter weights and connecting rod caps running in oil. This can cause overheating of the oil supply due to the crankshaft directly transfering heat to the oil supply, and can effect the hydrodynamic wedge thats created between the bearing and the crank journal and can cause non-reversal of the crank pin. I have 16 years background in large natural gas and diesel engine technical services and shop/field overhaul and troubleshooting, so I have a little bit of knowledge. Cutting back to about 13.5 - 14 qts has taken the noise out of my 6.4, I would like to hear if this is true for some of yours. Repost and let us know."