i just got done with 2007 5.4 Triton with cam phaser noise
i replaced phaser, timing chains ,tensioner, oil pump,
and it still made noise at idle when it was hot
so a change the oil to 0w40 and my noise went away .
5w20 starts to brake down at temp of 180 but 0w40 works up to 212
ford will tell you all you need is 25psi of oil pressure what i have seen is you need at least 40psi of oil pressure so if you have noise try 0w40 mobil1

 

40 psi at idle is pretty high, something else is going on.

 

Interesting results. I have a 2006 f150 fx4 with the 5.4. When hot it sounds like a rod knock, it goes away past 1200 rpm. I have not checked the oil pressure yet. I'm debating whether to change just the Phasers or do the whole timing chains, tensioners etc. It does have 100,000 miles. A switch to 5w30 did not help. I'm willing to try a 5w40 or even a 0w40 before I Tear into the engine. It runs great other than the noise. Any thoughts?