​ ​Here is the  explanation of the Western Digital  WD series code to identify. It will seen on the part of the model number after the hyphen, usually in the 3rd, 4th, and 5th characters. For example, for this models such as WD5000AAKS-40V6A0, the series code is V6A, which belongs to the Tahoe Families, as shown below:

WD HDD Families : By Code After Dash

This will help you find other models in the same series that are compatible with head and PCB replacement.