Hey Guys, thanks for the welcomes and thoughts. I wanted to update you on what ended up happening with my GC.
After getting towed to a small dealer in Flagstaff, Arizona (remember the line from the Eagle’s song “stranded on a corner in Winslow Arizona….?” Yep, next town over) we waited 4 days for them to even look at it. This was the point where I reached out to you all about them wanting to drop the trans. I wrung my hands for a day deciding whether to let them go ahead and potentially run up a lot of repair bills, but in the end I decided to gamble on the problem being what I thought it was, and being covered under my extended emissions warranty.
Well… turned out that I incorrectly self-diagnosed the problem as the turbo coolant inlet pipe, but they found that the turbo coolant return hose had blown (pic of old and new posted). I was really surprised at this because I had not run across any mention of this part in any of the ecodiesel forums I follow. Luckily, it is still part of the “turbo charger system and related pipes and hoses” mentioned in the warranty docs, and the dealer had one in stock (minor miracle) and replaced it under warranty.
So, this chapter has a happy ending. I went ahead and ordered the high temp silicone hose and clamps to eventually replace the inlet hose under the intake as I i figure it will need it eventually. I still have around 8k miles of extended warranty left; maybe I’ll get “lucky” and it will fail before that runs out LOL!
Thanks again for your replies!