I will second Coby's recommendation.  The chemistry of coolant is very
sophisticated.  When new the formulation "permanent" type coolants were
introduced by the manufacturers a few years ago the "permanence" relied
on the new coolant reacting with the NEW, un-corroded, metals in a NEW
car.  These only were effective in NEW cars as the first coolant ever
installed.

I don't know if Prestone has done something different, but I would not
risk putting anything but the Autobahn coolant in a waterboxer.  I do
however use a product called No Rosion
(http://www.kars.com/showcase/no-rosion/) for additional protection.
Worked for me so far 90,000 miles.

Michael Townsend wrote:
>
> Interesting . . .
>
> That is the first negative comment about the Prestone Orange Phosphate Free
> that I have heard.  Do you have any information, because I am using the
> orange stuff now in my VWoCanada rebuild.  I'd hate to lose my head gaskets
> in 2 years!
>
> Thanks,
> Michael Townsend
>
> -----Original Message-----
> From: Coby Smolens <cobys@WELL.COM>
> To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
> Date: Wednesday, September 08, 1999 9:43 AM
> Subject: Re: vanagon Digest - 7 Sep 1999 - Special issue
>
> >In our shop we use ONLY the Autobahn coolant from VW. I have seen too many
> >new cylinder heads leak due to corrosion after VERY short periods of time
> >(like 2 years!), the installer having used other phosphate-free coolants
> >such as the famous orange stuff that's out there (Prestone?)... The VW
> stuff
> >is not just a sales gimmick. It is formulated for the particular alloys
> used
> >in the heads and case of your waterboxer. It's expensive - $15.00/gal - but
> >it doesn't cost so much if it _stays_in_the_engine_.
> >
> >Coby
> >
> >Valley Wagonworks
> >"Intimately acquainted with VW Vans since 1959"
> >
> >Volkswagen Bus, Vanagon, Westfalia and Eurovan
> >Repair and Service Specialists
> >
> >1535 Sir Francis Drake Blvd., San Anselmo, CA 94933
> >Voice:(415) 457-5628
> >Fax: (415) 457-0967
> >http://wagonworks.com
> >mailto:contact@wagonworks.com

--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext 208

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