here's an update to the transmission noise i have. 2019 6.2 lt, 10 speed
a few weeks ago i noticed a whining noise when i put the truck into drive (and reverse). you could hear it as it went through the gears, but no other symptoms. last week, the trans started clunking occasionally during downshifts. then started slipping and surging at low speeds with in town driving (not consistently). took it to the dealer last friday. they think it's a torque converter issue and are replacing that.
this particular dealer said they've not seen any of the 10 speeds with issues. they had to call a GM tech to help diagnose the issue.
parts are supposed to be in mid-week, then a few days to do the work. hopefully that resolves it.