I’ve got the same job to do. 21 on both sides has deteriorated with large chunks missing. I have had the new pieces in my shop for a year, but have always found a reason to put this job off. I read something about it at some point that lead me to believe the window didn’t need to come out.

On my extended list for my x5 is a paint job, maybe, so I’m stalling until I decide for or against that work.

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Current
Original owner 2002 E53 X5 4.4i to 4.6i swap
2025 G06 X5 50e
Former
1972 Audi Fox
1986 Saab 900S
1996 BMW Z3
1998 BMW E36 M3 Sedan
2004 BMW E46 M3
2006 Audi A3 Quatro
1993 Mopar 318 Jeep Grand Cherokee
2015 V6 Jeep Grand Cherokee