Greg wrote:
>
> Ian Rawlings wrote:
>> No, you need "rubber grease", the combination of normal grease, rubber
>> and brake fluid isn't a good one and will lead to the seals perishing,
>> so get some "rubber grease". You should be able to get it from a
>> motor factors.
>
> Thanks to everyone who replied, I'll get the proper stuff for the job.
> I just wondered if the 30 year old manual was still valid given that I
> thought they stopped using seals that were vulnerable to mineral oil in
> brakes years ago, from a quick Google it seems not.
>
> Greg
There are probably a few cars that do use mineral oil for their brake fluid
- I think hydraulic suspension Citroens do for example, and there may be
others, but in general, as you say "it seems not". While I am sure it is
possible to make a satisfactory system using mineral oils and synthetic
seals, there is probably little pressure to do so - why change unless there
is a strong reason to do so, particularly with the probability of mistakes
in fluid being made with a critical safety system. Citroen probably got
away with their change (in 1967 from memory) because it was not just the
brake hydraulic system - the same system runs brakes, power steering
suspension and (some models) gearbox, so there was less likelihood of their
fluid being confused with brake fluid.
JD