#1. It was 85000 miles on a.Gen 2 engine...2018 Navigator L
#2. Vehicle is a work truck in the livery industry.
#3. Ford in its manual said the engine would have no problems with 10k mile OCIs so I went 7k mile changes using Valvoline full synthetic maxlife.
#4. The delays at the dealership were as a result of part backorders. I was told I was like 1000 on the list for some of the parts. Dealership treated me ugly...not happy to see this repair project. Also only a certified tech could do the work.
#5. Yeah the 5 liter is probably a better engine until Fords turbo technology improves. If I had a choice would rather go with a natural aspirated engine.
#6. If you go into a forum dedicated to a certain brand or model dont bring issues. It was funny. I honestly thought Ford owned the F150 forum as I was not welcome to post problems about the trucks. As soon as I posted problems mods were right on top of me.
#7. Took dealership two repair tries to get it right.
Lastly here is part of the dealership parts list. An extensive job.
Im going to experiment with different oils and have Blackstone tests run.