I am not sure that dex-cool works as well at cooling.
The viscosity seem a bit high so that it may cycle at
a slower rate so I would avoid mixing above 50:50 but
I am sure that when the green stuff begins to seap
past the seal it will corrode the heads as the
phophate salt is corrosive.   The dex-cool does not
salt out when it begins to seap
but behaves more like a soap and will not corrode the
head.   I have not seen any evidence of the orange
stuff leaking out anywhere and it has been over 5
years.   But I could imagine if your mixture is too
high you might see a higher temperature and pressure
gradient that could cause leakage.   Like I said I
think the organic nature make the mixture flow to the
radiator more slowly and this could be a problem.
       gary
Date:    Wed, 24 Oct 2007 16:14:52 -0400
From:    Walt Spak <b20swalt@CITY-NET.COM>
Subject: Re: Dex-Cool . . . I hesitate to ask this

List,

I will take this a step in another direction.  I have
replace plenty of
Vanagon head gaskets as I am now running my 19th.  I
don't see any
indication that the coolant corrodes the heads at all.
 I have never
seen any corrosion in the water jacket areas of the
heads.  I have seen
corrosion under the rubber head gasket which leads me
to believe that
 it
is condensation that corrodes the heads.  I think that
a bus that has
made more short trips than long trips is affected
more.

Walt

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