You're correct in everything you say except that brake fade has nothing to
do with brake fluid.  It has to do with the changing coefficient of friction
of pads (especially organic) as they heat up.  Two different phenomena,
neither one pleasant.

Karl Wolz

----- Original Message -----
From: "Kent Christensen" <lkchris@USWEST.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, May 20, 2000 12:32 PM
Subject: Re: Brake fluid replacement

> re:  Change it at least every two years because it attracts moisture
> (what does this do?)
>
> When they are used, brakes get hot.  Water boils at a lower
> temperature than brake fluid.  If water in brake fluid boils, it is
> just like having air in the system--boiled water is a gaseous matter
> state, just like air.  Unlike liquids, gasses are compressible.  Push
> pedal, air compresses, no brakes.  This is known as brake fade.  It's
> bad.  Especially coming down a mountain or the like.  Rust is the
> least of your worries.
>
> PS:  In a recent NASCAR auto race, front brake discs were seen glowing
> red.  "The Professor" reports brake engineers advise this requires
> 1300 degrees F to occur.  Water boils at 212.