Sure you already compared the problem window to others that are working. I went and looked at mine though. I see nothing in the track. It just has the two lips that retain the rollers. Thought maybe it was just upward spring tension on the roller arms that might just keep the rollers pressed upward and into the track. I tried to carefully pull my roller arms downward to see if they would just take the rollers out of the track. Nope, they are very much retained in the track by the two lips that run the length of the track. Have you run your fingers along that lip to check if it has a piece chipped out, that would allow the rollers to pop out? Are the rollers maybe damaged? Are the roller arms moving like they should when you turn the knob? That part might be damaged, and not expanding & contracting as designed. Sorry I don't have the answer.
2016 RAM 2500 Cummins SLT Lone Star 4X4 LB
2016 Windjammer 3029W Platinum
I'm not an expert. But I play one on the internet.
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