Eric,
Quit speculating and pull the door trim panel and find out what is wrong. If
you keep running the window you may break something. If it hasn't been
opened in 20 years than it definetly needs to be lubed. The lower attachment
of the lift mechanism into the door sheetmetal is a crummy design and
eventually the sheetmetal deforms and tears when the window binds and is
misadjusted. Ask me how I know. Be careful pulling the door trim or you will
break the forward mounting tab on the map pocket. Let us know if you need
further directions on this. Good luck.
Ralph Wasserbaech
'83 300CD my car
'90 300D '01 E320 Wagon wife's cars
'82 300TD parts car
'82 240D (just sold)
'82 300TD currently smashed