Please help

[whitebenz15]

1991 SL500 driver window is very slow coming up or won't close all the way when the soft top is closed but will after you drive for a while. Now it won't come up at all unless with the raising of the roof. Any ideas? Appreciate any suggestions. Always rather know the problem before taking it in. Thx.

[tecqboy]

In my 91 300SL, the grease on the window regulator mechanism had dried out and become more like glue than grease. This made operation very slow. I used solvent to clean the old grease off, then re-lubed with lithium white grease. Unfortunately, to do this requires dis-assembly of the door panel, a major job. Of course, you might also have a faulty motor or switch.

To remove door panel 1991 300SL.


1. Carefully remove the door lock knob by pulling outward ( parallel ) to release.
2. Using extreme care, remove the wood trim behind the door release handle by lifting outward with a panel removal tool.
3. Extract the single screw securing the metal trim behind the door release handle.
4. Remove the single 10mm bolt securing the door latch assembly to the door.
5. Carefully remove the seat control assembly and wood trim on the door panel using a panel removal tool and prying outward on the outside edge.
6. Remove 1 screw from inside the door pocket on the outside edge of the door in the pocket hinge assembly.
7. Remove the single very small screw from inside the pocket on the inside edge of the pocket securing a piece of plastic molding. Remove the molding and extract 1 large screw securing the door pull handle and panel to the door.
8. Extract 1 screw securing the black trim piece around the door latch. Lift up from the bottom to remove.
9. Extract 3 small screws securing the chrome trim on the top of the outside edge of the door panel and remove trim.
10. Remove the courtesy lamp assembly at the bottom of the door panel by snapping it out with a panel removal tool.
11. Using a panel removal tool, carefully release the “pop” fasteners from around the perimeter of the door panel. Lift up on the door panel to release the metal clips from the top edge of the door panel.
12. Slide off the vacuum hoses from the connectors near the panel bottom.
13. You are now holding the free door panel.

Reverse steps for installation.