When I recently had four windows de-fogged at RV Fog Doctor I questioned why they did not use butyl tape between the window frame and the coach wall when they put the windows back in the coach. They told me they never use butyl tape, 'hate the stuff'. They said the window frame had a foam seal on the back side and all they did was put a bead of silicone around the frame after it was installed.
Two weeks ago while at the Country Coach service facility in Oregon, I asked them about how they sealed the windows when the coaches were built. They also said the frames had a foam seal and all they did was seal the outside with silicone. CC did remove one of my windows to treat rust on the metal frame around the window (I saw that at RV Fog Doctor when they had the window out and they did a sorry job of treating the rust). CC did tell me they replaced the foam seal on that window.
I know that my Winnebago Journey had black butyl tape or sealant behind the frame along with a bead of silicone. I'd prefer to use something like Pro Flex sealant and not silicone.
'07 Country Coach Allure 470 Siskiyou Summit #31578, Cummins ISL 425; 2014 Ford F150 toad; Air Force One Toad Brake.
Glen Allen, VA; Smith Mountain Lake, VA.