After all the write ups you post this? Listen first of all its probably nothing more then a VCT Solenoid sensor that is bad. Second of all missing and rough idle will all cause the problems you relayed. Do not put thick oil in that motor. You'll ruin it. Check coils, plugs and those two sensors... how many miles is on it? Extending the life? The cam phasers go out it just ticks... I know a guy with 250K+ his has ticked since 90k it sounds awful but runs great, and its fine. Ticking should go away after a certain amount RPM's should be fine after 1200... at 1200 these trucks make a slapping sound almost like something slapping together inside the motor. A brand new one with no miles will do this. Its the nature of the beast. If the ticking stays even after 1000 RPM's and is noticeable through all RPM's The VCT sensors are bad, which are common on these trucks.
My ride:2005 Ford F250 Powerstroke 20" rims wrapped in 33's, 155k miles. Spartan Tuned for now...
(SOLD)2004 Ford F150 FX4 Crew Cab Black 3" HBS Level Kit, 5star tuned 93 perf, with 155k miles, ran 9.98 1/8 mile at 76 mph