Hey guy's, how's it going? Just one easy question. Can I use a fernco donut to connect 4" pvc to a 6" clay waste line or do I have to use a fernco o-ring? I'm looking for the easiest way.

Thanks guys.

Will you be going from 4" to 6" and not 6" to 4"?
If from 4" to 6" you're good to go.
TIP!
Take a file and bevel the edge of the PVC and use plenty of heavy lubricant on both the pipe and gasket.
If you have a hard time getting the pipe started it's acceptable to shave off a few ridges,
Good luck, Tom
PS. Over the years I've connected drainage many ways but the method that gave me the most hassle was joining cast iron with donuts.