Have a 1984 300sd.Does anyone know if it has a speed sensor on it and where it might be located at.

I am thinking that you are referring to a device other than the speedometer - for Anti-lock brakes perhaps? those would be at the wheels, if you have ABS. Look behind the backside where the tie rod end is connected...within an inch or two, there would be a sensor; it is held in by a single bolt. Do not confuse it with the brake wear sensor gadget, which is also held in by one bolt, but is higher up.

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09 Jetta TDI
1985 300D

If you're looking for the cruse control speed sensor, it is mounted on the backside of the speedometer, near the area where the cable attaches, it has 2 wires (1 plug)

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