Thicker bulkhead gasket

[raultsu]

Is there such a thing as thicker sch40 bulkhead gaskets? I know sch80 are thicker but I don’t think you can use them with sch40

 

[X-37B]

Yes you can use a scheduled 80 gasket on a scheduled 40.
Why do you need a thicker one?

 

[raultsu]

I have a small leak from one of the gaskets going from the tank to the overflow. I figure is I have to take the overflow off I might as well use a bigger gasket.

Yes you can use a scheduled 80 gasket on a scheduled 40.
Why do you need a thicker one?