I am having the same issue.
I have a 2015 Sierra all terrain 5.3L
60,****** miles on it.
Brought it to dealer with Check engine light, traction light, smoking, shaking, etc.
dealer said I have a bad injector. $1300
i said ok. After waiting a week for the parts to come in. They started to work on it and then call me saying I have 2 collapsed lifters on 1 side.
They also say my power train 5/75,000 is expired
obviously I’m well under 75k but it’s 5yrs 8mo old.
service manger says they’re gonna “talk to the rep” on Monday and see if they can get it covered for me.
is there any chance they will fix this ?
or should I prepare for battle ?
thanks