Date: Thu, 17 Feb 2005 12:55:15 -0500
Reply-To: Dennis <guskersthecat@YAHOO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis <guskersthecat@YAHOO.COM>
Subject: Re: where is the best buy for drums and rotors?
A couple of thoughts come to mind on this question ... coming mostly from
my VW racing efforts and common sense.
First, very few people follow the recommended brake fluid procedures, which
is a flush and replace every two years for most cars. This alone makes a
huge difference in braking effectiveness. For a vanagon, this is a good
idea. With brake fluid's (non-silicon types) hydrophilic properties, water
is absorbed agressively everywhere in your brake system meaning under heavy
braking, water turns to compressible steam, and your braking effectiveness
drops appreciably. In my mind these fluid changes are an absolute
essential in terms of safety and brake system corrosion control.
I can appreciate Dr. Tim's advice on OEM brake pads. As many of you
already know, there are lots of different formulations for brake pads be
they organic, metallic, or carbon. There are trade offs with respect to
pad wear, disc wear, operating temperature, dust and so on with each one.
A good example of this is race type pads that tend to perform very poorly
until heated, but then have better fade resistance. The first time trying
a "cold" stop with these pads, you appreciate why they are not suggested
for street use. Any pad offering longer wear is generally a tradeoff with
respect to braking effectiveness or disc/drum wear. Whenever you stray
from OEM pads, I believe you need to take some responsibility for what
happens or doesn't when you use the brakes. As far as the disc/drum
themselves, there are far fewer variables involved. IF they are designed
to spec, the only differences I see are variations in steel (corrosion,
wear). For example, most seem to agree there are metallurgical differences
between brazlian vs german parts.
Given that brakes work by creating friction, and are limited by how well
the system disipates heat, it doesn't seem safe to leave rotors and drums
near their wear limit on the vehicle. The "missing" metal is also missing
mass, and therefore less heat absorption/dissipation.
There are so many variables with respect to "consumer" brake jobs, it
doesn't surprise me to see so many opinions. To conclude this lengthy
monologue, my suggestions:
1. Flush and replace the brake fluid.
2. Go aftermarket on the metal parts (save some $$)
3. OEM dealer on the pads.
Having said all that, I have no illusions to the effect that OEM is always
best...very often it's not for my applications. However, OEM is usually a
known quantity where aftermarket can go either way.
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