Yes that has been my experience. Most shops quit blasting in our area mostly due to EPA and the labor cost. I do small parts for work. And the big shops have to send all blasting out. We tried doing etching but rework was causing a big problem for us. Of course powder age and quality play into...
Agtec Automatic Vent Opener - 30 lbs https://share.google/YXPGVdRBaK1ndMM5o
We used to adapt them to intake louvers, kinda upside down of how most photos show them being used
This may or may not have a bearing on your truck, I know the GMT900 Subby with rear entertainment have this issue and changing the rear control panel fixed this issue for me
Obviously a few years different but not sure how different they are.