Felt doughnut on balancer

This thread is a couple years old but here’s some information. I too was confused by the felt “donut” so I searched and came up with this thread. Most everybody leaned to putting it on the outside but there were a few who were animate that went inside between the oil slinger and the backside of the case. I didn’t find the definitive answer I was looking for.

I called the Felpro tech line and spoke with Eric. He says it’s a dust shield that goes between the rear of the harmonic balancer and the front of the case. It’s designed for heavy dust applications but fine to use in everyday situations.

I hope this helps for those with similar questions.