Caulk used at factory

From my expierence...They use a typical butal tape underneath the flanges, usually about 3/4"wide. Then they seal the outside of the flange with Geocell clear to keep the butal from oozing out of the flange. I will tell you getting Geocell off of the flat surface is extreamly dificult. This stuff bonds beyond belive but over time you will see some seperation from the flange where the Geocell is thin. Are you worried about leaks?.. not likely IMHO but use a heavy duty plastic scraping tool, usually the blue kind and mineral spirits...be prepaired for a lot of work. Not way off topic but there is a good STICKY over on the Truck camper forum. At the top of the page you will see the stick topics..Look for this:...good topics on what your looking for.
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