Bought used 2019 Denali Oct 2024 with 41 k miles on it. 1200 miles later started feeling vibration under load on highway. Took to dealership and they said I needed to replace torque converter. After that the transmission went out during test drive. Then waited 45 days for new transmission to find out the unit was defective. Now we’re going on 5 months and the truck still waiting on a replacement transmission. GM hasn’t acknowledged any of my complaints about this and said that they’re doing the best they can for me and is going to award me 10000 reward points for future use! What a joke! 5. months to replace a transmission? GM has completely failed its consumers, at least this one!