Head fire rings

[Scooby d]

Thanks for the info ! A local shop suggested the fire ring thing to me and I was skeptical. My truck is still factory tune at 600 hp with all egr dpf still working. I have did the egr/dpf tuneup every spring and have learned how to take care of it but it still gives me some trouble. I use my motor in heavy haul so it gets a work out. I'm loaded between 130k and 200k every day with a lot of pto idling time so it gets abused. Lots of oil changes because I run between 2 to 3.8 mpg. I will pull the head today and see what needs done. I have moisture on the intake and exaust valves in number 6 and a dribble of oil on number one valve stem. I'm guessing a liner hight problem will be the issue. If I have to fix liners then I'll be throwing lots of new parts in it. Thanks rawze for that liner hight info.. I'll be checking that out.