It does say lines and hoses are not included on the warranty. Which is fine however they should not have said it's covered, did the work, then said hey bad news turns out it's not covered and you owe us $1200 Merry Christmas.
Well just goes to my opinion on manufacturer warranties. They are trash, luckily I have mechanical breakdown through GEICO and they are covering it minus the deductible.
Update: dealership just called back. Said it is now not covered under warranty and the bill is $1600. How is a transmission line not part of the power train?
Line broke while driving from NC to Florida. Luckily it is all covered under warranty however the shop has had it for over a week. I understand with the holidays there are a few days off but how long does it take to swap out a line.
Range Technology AFM/DFM disabler device part# RA003R. Came off of my 2020 Sierra AT4 with the 5.3. $160 shipped.
https://www.rangetechnology.com/products/afm-dfm_disabler/parts/RA003R