Hello! With an almost 18-year-old vehicle I wanted to change the brake hoses in the rear. I sprayed the screw connections with rust releaser several days before, so that it can work. Nevertheless, I had difficulties in loosening the screw nuts and also easy heating did not bring so much improvement. I moved the brake line key back and forth again, used rust releaser again and again etc.. It seemed to me that the overwound In particular, I had problems solving the screw connection. I then applied some force and finally managed to solve the roll-over nut. However, with the roll-over nut, which I wanted to solve, the brake line also turned a bit with it. Because the brake line is fixed in several places and I also held it, of course, also force on this a This means that the coating is broken / damaged and it seems that the metal in the area of the screw connection could also have twisted a bit. Now I wonder if the respective brake line has been damaged by the deformation or can easily be used further. According to what criteria can you judge that? I have now got the nut relatively common again, so that I can probably tighten it easily. e. Otherwise, the brake line is fine. Only in the area of the nut is this almost blank. What should be lubricated on it if necessary? I ask you for detailed advice. Thank you!