When I was a teenager I put hydraulic shock oil in a '37 Chevy's brake
system.  It ruined the rubber in all the wheel cylinders and the master
cylinder in short order.

You do want to make sure that what ever you use is compatable.

Mike

Jonathan Farrugia wrote:
> so i'm parting out a vanagon and i want to save the hydraulic components
> and i don't want them to be rusty on the inside when i decide to use them.
> so i was thinking of draining the system and flushing it with some kind of
> oil/fluid that is not hydrophilic.  i was thinking hydraulic jack oil or
> some other type of thin generic oil.
>
> i mentioned this to reputable local shop and the guy there suggested that
> some petroleum based oils might cause seal swelling.  he suggested using
> mineral based oil like the pentosin used in the audi power steering
> systems.  we also discussed using silicone brake fluid since it supposedly
> doesn't absorb water and silicone paste is what you use when you build
> hydraulic brake components and put them on the shelf.
>
> any suggestions and comments on the issue would be great to hear.
>
> jonathan
>