curious what you are referring to as the viscous coupler and when you say it went, what it's doing (or not doing...)

 

Late in 2017 I started to hear a clunking sound from the rear of the car. Mechanic indicated he thought it was the viscous coupler. Attached is the description on his invoice from January of 2018. Mileage at the time was 214,000. I decided at that point in time it wasn’t worth the cost to fix it. I figured once that broke, I would get rid of it. It broke about a month ago. Current mileage is 230,000.

The clunking sound has stopped. There is now a whirling/rubbing sound.