The most reliable way to determine the transmission manufacturer is to:
1. Check the Identification Tag: Look for a tag on the transmission case itself. This tag will have a number that can be cross-referenced with Ford or Mazda parts catalogs (online databases are your best bet here). The tag might even explicitly say "Mazda" or have a Mazda part number.
2. Examine the Transmission Case: While not foolproof, Mazda transmissions often have casting marks or numbers unique to Mazda. However, this requires familiarity with Mazda transmission castings and would be difficult without reference materials.
3. Check your Vehicle Identification Number (VIN): The VIN contains coded information about the vehicle's specifications. While it won't directly say "Mazda transmission," decoding it using a VIN decoder (many online) might reveal the transmission type, and from that, you can deduce the manufacturer.
4. Consult Repair Manuals/Parts Catalogs: Using a repair manual specific to your 1987 Ford Ranger will show you diagrams and part lists for the different transmission options available for that year and model. Matching the parts to what you see in your truck can help identify the transmission.
In short, don't rely on visual inspection alone. The identification tag or cross-referencing the VIN is the best approach.
