[locomaro]

Just spoke to the body shop manager @ my dealership to get more specifics. Apparently they had similar issues with the Avalanche a few years back. It had a similar plastic gray piece that owners would have painted, but over time, the paint started coming off in sheets. Has to do with the texture of the plastic used, which apparently cannot be fully sanded & primed because the texture is not smooth to start with. He explained that even if you sanded the 'peaks/bumps' off the top, you'd still have the 'valleys/divets' below the surface which is what causes problems with paint adherance over time.