Looked online for advice and found AppliancePartsPros.com. Looked thru their list of fixes and diagnosed the issue. (Properly, the first time!) Took the agitator off as per instruction in their video and discovered one pawl of the top agitator ratchet was broken. The short cam kit had all the parts necessary. Cam and the thrust spacer washer looked a little worn, so all were replaced. The order arrived in three days. In the interim, all the parts to be reused were cleaned and prepped. When the parts arrived, the repair took about 10 more minutes. Total time of repair and cleanup is about two hours of easy work. Spent more time cleaning and studying than fixing.