For the sewer clean out that I need to put in, I put the collar on a 4 inch pipe to test it, and even with clamps loosened all the way, it was very hard to slide the rubber part on to the pipe. When I put the clean out in place I will have to slide the rubber part halfway off the short piece of pipe connected to the clean out, and at the same time on to the existing sewer pipe. That will be really hard, at least for this novice. I don't doubt that using anything slick like grease or petroleum jelly would be a bad idea, but could I use water? My GUESS would be that the water would dry out soon. Especially since the sun will be hitting the pipe because I do not plan to fill in the dirt for at least a few days so I can make sure there is no leak. Any thoughts?