Hello together, after there is now the new GG40 or G13, which should be backward compatible, I would like to know if someone from you is already using it, instead of continuing to rely on G48 or G11 for the v8 engines from the 60s and 70s? The durability and ability should last longer and furthermore the stuff should be backward compatible with all others, which should not be done to preserve the new better effects. After I have read myself in many times now into the Discussion of which water should be used remains at the end the following insights: Distilled water is often recommended, but is slightly acidic and should not be taken. In case of rainwater it looks similar. Tap water always works, best if it is not too hard, if it is too hard, one hopes for the decalcification effect of the frost protection, but should possibly look for alternatives. If one wants to be sure, one takes finished mixture, whereby I assume that the the “real” water was taken there, so just tap water was mixed with Smile The criticism about the finished mixture and the fixed predetermined ratio I can not follow, because then I just tip if necessary still biterl concentrate to it .-)) Mineral water is often only discussed in connection with emergencies, but I would like to throw up an idea here. Why not take a silent mineral water, which has a neutral PH value and a narrow water hardness? h but also nowhere found anything in the net. That would be the preferred solution for me if one lived in the area with water hardness over 18-19. What do you think about it?