What's the trick? When I lower my drivers side window, the regulator does not take the window down with it, causing gravity to make it fall down ofter a second or two. Obviously the window pane is not seated properly by the regulator. Thanks in advance.

After a second or two? Then freefall? To where?

There are bolts that hold the regulator to the door, that hold the stops for the regulator, and that hold the window with its metal base to the regulator.

My first thought would be that the bolt that holds the window to the regulator is loose, so the regulator goes down and then hits the bottom of the hole where the bolt is in (bolt is there but loose), at which point it just gets dragged down. There is enough friction in the window track t hold it before that.

The system is pretty simple. It is just three standard MB bolts, 10mm IIRC holding it all together. THe regulator does kind of fit into the metal on the window, so it is plausible that the window is still supported in some positions.

Only way to find out is to pull the door panel. Easy job, takes less than 10 min, and gives you a chance to re-seal the vapor barrier, which is likely a smart move.

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