I don't entirely know the symptoms of this but if the Kick Down Switch sticks it messes with the shifts; this is the one that if you press down on the Accelerator Pedal all the way drops you into a lower gear.

If you can't tell if it is sticking in the ON position trace the Wires and see if you can disconnect it at the Connector. I am guessing there is another Connector down on the side of the Transmission where the Kick Down Solenoid is.


It also might need to have the Transmission Filter changed. Unlike a lot of American Cars from the past that seemed to only have a fine mesh Brass Screen for a Filter the Mercedes actually has a Paper Element Filter.

Then there is the Bowden Cable that attaches on top of the Valve cover. That is supposed to adjust at what rpm the shifts happen at.

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84 300D, 82 Volvo 244Gl Diesel