Upper grille came off and fractured windshield while going down the highway it is a non serviceable part by GM which I believe is strategic seeing that they’ve had issues with earlier models of the the truck you have to buy an entire replacement grille for one issue that shouldn’t be happening was never able to locate part, I assume plastic grille clips dry rotted noticed the part lifted a bit before the entire part failed thought someone was trying to break into my truck . The wind while going down the highway caused them to fail, I’ve seen multiple GMC sierras with the same grille issue, I uploaded before and after pictures of how the truck looked before and after pictures .