Anyone else with this issue? Interior silver bits fading

GMB14U2NV

On the door sill plates : From what it looks like it is moisture born water staining/etching. Either you have very high humidity's and are developing a condensation pocket between the inner seal and outer seal on the door, or you have a seal on the bottom of the door that isn't really making a good seal and that could be car wash soap etching. I saw this on another one of my vehicles a long time ago and found it was due to neighbors sprinklers hitting the bottom of a door seal just right. It etched the chrome stepper plate.

As for the rear brace bar : I say it's Humidity mixed with AC cold temperatures causing condensation. I found water beads once in mine after we had a mid 90's rain and I had AC full blast. (Just re-adjust the air vents to not shoot at the brace bar so much??)

To remove possibly : Use a diluted CLR and water mixture - or a "water stain" remover. clean that off thoroughly when done. Then get either a silicone based oil or WD-40. Use a rag and just wipe the surfaces to prevent any future spreading or moisture born etching.

Always wipe out both door jams after washing with any kind of pressure sprayers or even garden hoses. And again wipe with the silicone oil or wd-40 rag. Doesn't have to be an oil slick - but just a light dressing if you will.... Like armor-all on a dash.....

That's my 2 cents......