Silicate is not a lubricant, it is an abrasive, (silicon like from sand). It
is not used in the newer vehicles as it was found to wear through heater
cores and radiators. It function was to control corrosion through abrading
it a way.  I changed my Vanagon over to the Prestone Long life at 132K. The
water pump was last replaced at 96K and it now has almost 180k on it. So
let's see, 1st water pump at 49K, second at 96K, 180K now and still going
strong.  I doubt the antifreeze was the cause of the premature pump failure.

Dennis

----- Original Message -----
From: Dana Morphew <kdm@WHIDBEY.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, December 03, 1999 9:25 AM
Subject: Re: CHEAP Silicate/Phosphate free anti-freeze

> I just installed the Prestone 5/150 ExtendedLife, orange, silicate and
> phosphate free coolant.  Where might I read about the silicate
> requirement for our waterpumps?  Thank you.
> -Dana-
>
> dave wrote:
> >
> > You do not want to use a silicate free coolant in a Vanagon.  Silicate
is a
> > lubricant that is necessary for the waterpump.  I made the mistake of
using
> > Autobahn silicate/phosphate free (pink) and burned up a waterpump in 20k
> > miles.  The correct coolant is Autobahn phosphate free with silicate,
which
> > is blue.  It is my understanding that all new VW's are now designed to
use
> > the silicate free coolant.
> >
> > dave
> > dave@251.org