I learned something new yesterday that I am guilty of. You cannot just replace Dot 3 brake fluid with silicone fluid. If there is even one drop of 3 in the system it will seriously swell all the rubber parts it comes in contact with. Only way to add silicone is in a completely new system. My friend had examples of what it will do. I never knew that and have done it. He is friendly with a major antique brake rebuilder and if you plan on using it you have to let them know so the parts are assembled with silicone. I was blown away by it.