Yes,

Rear heater valve, connection to the rear heater core.

Eric 

> On Oct 13, 2021, at 5:13 PM, John Rodgers <jrodgers113@gmail.com> wrote:
> 
> Is this the one in the rear heater?
> 
> On Wed, Oct 13, 2021 at 3:48 PM Eric Caron <ericcaron96@comcast.net <mailto:ericcaron96@comcast.net>> wrote:
> Hi Folks,
> 
> It took about two weeks but I received my O ring from GW.  I’ve replaced it before and it lasted about 7 years.  Low usage and miles though.
> 
> Are there any tricks to replacing it that makes it work better?  
> I clamped off both hoses.
> 
> I remember simply wiping down the surfaces, pulling the old O ring gasket and putting in the new one, and bolting together.   I’m just wondering why it lasted only about 5,000 miles and 7 years.
> 
> eRic