the groove is in pretty good conditions. A couple small bits have flaked off, but overal it seats the seal just fine. I can clean it out with dish soap and remove any dust/grime under the seal.. but it's not sticking. My local mechanic recommended some silicone glue as well, just to keep it down (very small amount). That way if i need to remove it.. it should be fairly easy to do so?

You think just adding some soap under it will create a seal?

The soap allows the rubber to slip past the locking area of the groove strip hence making the gasket sit in its full seated position and fully against the glass as well.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)