Hello, Im in the process of remodeling our basement shower. There is currently a 2' cast iron drain pipe the old shower pan was using. I have taken up the old shower pan and tiled walls back to studs. my question is i am getting ready to do the pre slope but i have a KOHLER K-9136-CP Square Design Tile-In Shower Drain how can i connect it to the cast iron drain pipe? The old shower pan drain was connected by some type of adhesive or JB weld no sure and the new kohler drain body fits tightly on to the cast iron drain but need to secure with no leeks. Thanks for any suggestions.

normally there is a ribbed rubber gasket the gets installed between the outside of the pipe and the inside of the drain. you grease it up and pound it in..

You have a drain that was designed to glue onto the pipe. You could cut the cast iron a few inches lower, use a no hub band to transition to plastic pipe then glue your drain onto the plastic pipe.