Itasca Gray tank problem

[03_Cobra_sb]

I have a 90 Itasca class C RV. On the gray tank exit fitting, there is a gasket that goes over it and clamps down. There is no rips in the gasket and it started to leak. Noticed the gasket had slipped and I readjusted it and tightened it. No leak. Then after driving on rough roads it did the same thing. Is there a sealant you can use with rubber and the plastic tank that will hold the gasket in place? or any other ideas?
Thank you for your help.
Chris

[ronfisherman]

I would not use anything that has Silicone in it. Future repairs will be hampered trying to get anything to stick to surfaces treated with it.

[pauldub]

I'd try contact cement.

[chilly123]

Might want to try some rtv sealant. Don't have to use a lot just enough to cause the gasket to stick to the surface.