Date:         Sat, 7 Feb 2004 11:38:05 EST
Reply-To:     THX0001@AOL.COM
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         George Goff <THX0001@AOL.COM>
Subject:      Re: wisdom of DOT 5 brake fluid
Content-Type: text/plain; charset="US-ASCII"

In a message dated 2/7/04 1:20:45 AM, jmeeks@GASLIGHTMEDIA.COM writes:

<< Could you elaborate on the "proper procedures" and perhaps any other
benefits of using DOT 5 >>

From my hard earned experience with DOT 5, the only proper procedure to
retrofit it is to completely disassemble EVERY component of the braking system and
thoroughly scrub them in hot soapy water.  Of course, after the cleaning all
has to be dried completely.  One problem is how to clean the internals of such
parts as brake equalizers and convoluted lines.  Another is how to swab the
brake hoses which have end fittings with a smaller ID than the ID of the hose to
which they are attached.

As I have proven to my self on two separate occasions, flushing copious
amounts of DOT 5 through the system will not remove all of the original fluid;
enough of the original brake fluid will be left behind in the numerous nooks and
crannies of the system to do damage.

DOT 3/4 brake fluid is hygroscopic whereas DOT 5 is not.  On the surface,
this might seem to be a very desirable quality, and it is, if it is used in its
uncontaminated form in a SEALED system.  But, a Vanagon does not have a sealed
system and since DOT 5 does not absorb moisture, bubbles of water will form in
it.  The density of water being greater than the density of DOT 5 will cause
the bubbles of water to migrate to the low points of the system where they
will collect to do their nastiness.

So, the proper procedure to replenish the brake fluid of a Vanagon with DOT 5
would be:
1/ Antiseptically clean the system.
2/ Fill it from a fresh container of DOT 5.
3/ Devise some manner to seal the system.

The alternative, which I recommend, is to flush the system with clean DOT 4
every few years.  When I was addicted to DOT 5 some twenty years ago, it cost
me $32 a quart.  I don't have any idea what it costs today, but I know that DOT
4 has to be MUCH cheaper with no palpable difference in its performance in a
road car.

George