[rheavn]

This is a common problem that has been "fixed" using different materials.  I give Ashley Pardue credit for finding an o ring that has resulted in both his and my sewer connection not leaking a drop.

You can source the o rings at:

McMaster Carr-Part #9396k227

or

Amazon--https://www.amazon.com/gp/product/B000FN1132/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Installation tip:  Coat the o ring with silicon grease and stick it on the stationary side of the Dupree sewer connection.  Bring the hose side up and tighten lock ring.  Lock ring is a little hard on the first connection.

I will report back on the durability of the o ring.

Hope this helps someone............................