Paint on half the roof gone, peeling in large sheets. Undercoat or primer looks shiny and smooth.Appears that the paint is not adhering to initial primer coat. So far, the rest of the truck panels appear very good, only the roof is peeling. Exterior has been taken care of and waxed with protective coating annually. I have noticed that the paint looked blotchy before this happened on the entire roof panel and I guess its all going to peel off. I am upset that we pay so much for a nice truck and then the paint peels for no apparent reason. If I go to a dealer they will probably shrug it off even though the rest of the truck looks great. I would like to know how many people experienced this and how many people were taken care of by GM. This was my third GM Sierra purchase. Maybe I ought to buy a Ford or Dodge next time.