To cure this you need to purchase some sticky felt and apply it to the bottom edges of the door panels where the hard plastic door panel "edge" meets the hard plastic door sill plates. There is also a spot on the front doors that can creak. Pretty much impossible to explain that location here on the forum. You can cure 99% of your problems by doing the felt on the door panel trick first.

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1984 300 SD 384,000 Miles