So I use RTV here and there for random projects, as I'm sure many BITOGers do. Now, if I have a larger project or something, for example a differential service, I'll likely go out of my way to grab a new tube of the appropriate RTV. Otherwise, I usually have some form of silicone RTV on hand from my last project. This comes in VERY handy. Unfortunately, it seems like they are always drying up and curing on me. Does anybody have a trick or method they use to extend the shelf life of an opened tube of RTV? How long can you stretch that shelf life out for?