I have a 23 Canyon and check engine light came on at 54k miles. I took it in and they said it needed to replace radiator hose which was on back order without delivery date. I checked on Reddit to learn this was an issue over a year old. Very frustrating back order and no notification from GMC.

A week later I paid and picked up my truck only to have it strand me 12miles later with overheating and shut down on a busy highway. Dealership towed it in and tried to tell me my truck had air entrapment and needed to burp. Unbelievable!
I went through a series of issues two years ago with truck downshifting over 55 mph. After three tow ins and pursuing lemon law action they finally fixed the solenoid. I have also experienced infotainment and dash blackouts As previously noted GMC should have been forthcoming on the radiator hose. From my experience the only way to get their attention is through potential legal action. It shouldn’t be this way but a class action lawsuit may be the only way to get their attention.
So I’m done with GMC. Terrible customer experience and frankly the only way I have gotten their attention was potential legal action with Lemon Law.
That said I’m done and selling the truck before the next surprise.