Don, Ok, so yours was replaced for rattle, not cracks or leaks. 3 weeks ago (about a couple months after getting the rear slider replaced) I too had water on my headliner. They just replaced the third brake light-which I would push for, not just the TSB that retightens screws. Our issues seem very similar (new slider to fix rattle and cracks/leaks, then third brake light leak). My replacement slider has no signs of cracks and it appears to not be leaking, however it's cold again in Michigan with no rain anytime soon. I have run through touchless carwash a couple times with no visible leaks (not since third brake light replacement) from slider. Here's a couple pics of third breaklight leak and repair. It seems that dealers will either remove and re-tighten the screws IAW with existing TSB, or just replace the entire third brake fixture for what is being diagnosed as a "third break light leak". Why the third brake light started leaking after just over a year from taking delivery and getting rear slider replaced is beyond me.
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