Location:
The transmission end of the cable will be located on the top of the transmission, near where the transmission output shaft exits. You might need to look underneath the van for easier access, and perhaps remove some underbody shielding. There's usually a fitting or a socket (often square) where the cable connects.
The instrument cluster end is, unsurprisingly, on the back of the speedometer gauge inside the dashboard. You'll need to access the instrument cluster (usually by removing the bezel surrounding it) to see the connection there.
Transmission Speed Sensor (NOT a cable):
Your 1990 Dodge B-150 van likely does not use a traditional speedometer cable like older vehicles. By 1990, many vehicles started transitioning to Electronic Speed Sensors (ESS). These are electronic components, not cables. They send an electronic signal to the instrument cluster, rather than a mechanical rotation.
The speed sensor for your van is likely located on the transmission case, near the output shaft, but it will be a sensor with electrical wiring connected, not a cable. It may be a single unit or part of a larger sensor assembly (like a Vehicle Speed Sensor). It's important to check your vehicle's repair manual or a parts diagram for the specific location of your ESS for the most accurate information. A diagram for a 1990 B-150 will be much more helpful than a general description.
Finding the correct part and information:
Before starting any work, obtain a repair manual specific to your 1990 Dodge B-150 van. This manual will provide detailed diagrams showing the precise location of the speed sensor (cable or electronic) and step-by-step instructions for replacement. A parts diagram will help you identify the correct part number. Using the wrong part will cause more work later on.
