I also believe that DOT 5 Silicone "should" be all right but the general consensus among the Delorean venders and service centers of other British cars say Castrol in the only way to go. If Silicone is working for you then stay with it. Just a couple of things to keep in mind. You can never get all the air out of the fluid so it is slightly compressable. This means a softer pedal and more pedal travel. On some cars it is an issue. If anyone is considering converting to it it is more complicated than just flushing out the old and sticking in the silicone. You cannot mix with other fluid types so it requires a rebuild of the ENTIRE system before using Silicone. You should make a label by the master cylinder so no one ever by accident adds anything but silicone to the system. Silicone is not hygroscopic ie, it does not absorb moisture so the insides of the system should stay pristine. Because of this it also has a higher boiling point than DOT 4. I would still flush it once in a while, maybe not every 2 years but every 10? It is also more expensive but not prohibitively so. Keep us informed as to how your experience with it is and maybe as brake systems get rebuilt more of us may convert to it.\ David Teitelbaum vin 10757 --- In dmcnews@xxxxxxxxxxxxxxx, "Bill Lane" <blane@xxxx> wrote: > Group, > > I have been using Dot 5 silicone brake fluid in my D for about 20 years. > The wheel cylinders, master cylinder and the clutch master cylinder have > been rebuilt once and the clutch slave cylinder has been replaced once. I > have seen no signs that using Dot 5 is causing any problems. > > Bill Lane > #3635