* Check the sticker on the driver's side doorjamb: This sticker usually contains information about the vehicle's specifications, including the transmission type (e.g., 4R70W, 4R100). Look for codes or abbreviations related to the transmission.
* Look at the transmission itself: This requires some mechanical knowledge and possibly getting under the vehicle. The transmission case itself may have a casting number stamped on it. You can then use that number to look up the transmission type. Be cautious when working under a vehicle.
* Consult your owner's manual: If you still have the original owner's manual, it should list the transmission type for your specific vehicle configuration (engine size, trim level, etc.).
* Use the Vehicle Identification Number (VIN): You can use the VIN to decode the information about your Expedition, including the transmission. Many online VIN decoders are available, although some may require a paid subscription. Alternatively, you can contact a Ford dealership; providing them with your VIN will allow them to pull up the specifications of your vehicle.
* Check the build sheet (if available): If you're lucky enough to have the original build sheet from when the vehicle was manufactured, it will definitively state the transmission type.
The most likely transmissions for a 1999 Ford Expedition are the 4R70W (4-speed automatic) or the 4R100 (4-speed automatic, heavier-duty). The 4R100 was more common in higher trim levels or with larger engines. However, definitively knowing which one *your* Expedition has requires using one of the methods described above.
