I would suggest that it is not a door problem but a window regulator problem that most of us coupe owners have had from time to time. It seems to be caused by closing the door by pushing the window instead of the door itself which causes alignment problems with the window. The regulators are repairable and you can find out how by doing a search.

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"Life is tough...it's even tougher if you're stupid." John Wayne


Dave
Pawleys Island, SC

'79 300CD