For more videos visit my website at
https://goo.gl/WdE91
Inside whirlpool washer agitators there are agitator-dogs. When the agitator-dogs are bad the top half of the dual action agitator will not turn and your clothes will not get as clean as they should. This video will show how to diagnose and replace these agitator-dogs.
https://www.appliance-repair-it.com/Whirlpool-washer-disassembly.html
https://www.appliance-repair-it.com/washer-agitator-repair.html