Casting numbers do not always correlate directly to one part number. One casting (number) can be the base for many different products. Casting numbers can also change depending on many factors. If the manufacturer moves plants where the item is made, many times the castings change.  The manufacturer may change something about the design, the casting can change also.

This does not mean that they don't sometimes correlate to one yoke and one yoke only.  There are many instances where they do.  Casting numbers most often are not the actual part number the manufacturer uses.  Flange yokes are many times the one type of yoke where the casting is correlated to one yoke.  We have many casting references on our site that you can check to see if you casting matches up to.  We have only put in verifyed castings in for cross references.  

Fail safe.......always check your measurements.