Re: TQC Brake Upgrade, DOT 5.

[Don Hoefer <hoefer@cary.eng.pko.dec.com>]

To All,

DOT 5 is hydrophobic, DOT <=4 is hydrophilic.  The problem with DOT 5
is that when water does get into the brake hydraulics it remains
separate from the brake fluid.  Causing rust in that location or
freezing in the winter.  Water stays in solution with other brake
fluids causing less rust everywhere and providing a lower freezing
temperature.  DOT 5 is used where there is regular maintenance
(racing) or controlled storage conditions (classic and antique cars).
The system must be entirely cleansed of the old fluid before DOT 5 is
installed.

Don Hoefer
'82 Coupe