My father and I purchased a 2004 F150 with the 5.4L engine. We are getting a knock/tap. Before we start really digging in, we wanted to see if anyone has had a similar experience or knows what this sound could be. We were thinking maybe a bad lifter or timing chain tensioner. We aren't mechanics by any means but wanted to tackle the job and learn along the way. Any input would be greatly appreciated!

See videos:

From top of engine:

Can see timing chain in this video..

From under truck:

 

Possibly Cam Phasers??

 

The sound wasn't that great on my end, so I'm sorry if I misheard. I just finished on my 04 5.4 3v with what seemed like a similar ticking sound. Took it to a mechanic, he couldn't help me narrow it down because there were too many possibilities. I decided to tear into it and figure it out- turned out to be a rocker arm with a stuck roller. A $13 fix (and a good 6 hrs- but I'm not too speedy!). For some reason, I heard the tick loud and clear with a stethoscope on the fuel rail.