In my opinion, you are much better off flushing the red stuff out. In time it will eat away any and all gaskets it comes in contact with. The stuff is bad news and highly corrosive. I think the only reason it gets put in from the factory is for job security. They figure most people will take the vehicle to the dealership to have it worked on, so why not make their visits more frequent with gasket problems... right after the warranty is up. Use the green stuff, it's tried and true and was engineered to stop corrosion.