Dexcool problem?

[Steve Manning <stephenm@ix.netcom.com>]

I switched to Dexcool a few months ago in my '90 200tqw when I replaced my
radiator and other cooling system parts.  I was not thrilled to read the
following information.  Read it and let me know what you think:

"Dexcool is an excellent antifreeze to be used in brand new cars in which
traditional phosphate/silicate antifreeze has never been used.  However, if
any traditional antifreeze has ever been used in your car's cooling system,
it is strongly advised to avoid using Dexcool.  This is because, short of a
dangerous strong acid cleaning or complete replacement of all parts within
the cooling system, it is physically impossible to remove all residuals of
phosphates and silicates - even with repeated flushing.  If Dexcool is used
in such a system, deposit formation will be almost instantaneous and will
seriously affect your car's cooling system eficiency and performance.
Because most corrosion occurs under such deposits, it will also affect the
long-term corrosion prevention in such a system as well."

(From the 'Tech Talk' section of the August, 1998 Roundel (BMWCCA
magazine), page 92.  This was an excerpt from an article written by Bill
Siuru in the May '96 Skinned Knuckles.  The excerpt is by Applied Chemical
Specialities Co, a competitor of Havoline, which makes Dexcool.)

Some of my thoughts:
- So, should I switch back?  Or is it too late?  Cooling system performance
seems fine.
- My car has always used phosphate-free antifreeze (as specified by Audi);
does this mean I don't have the deposits that cause trouble?  What about
the silicates mentioned?
- This information was written by a competitor of Texaco; I've never seen
Texaco state this information.  Is it correct?

So what does everyone else think?..............SLM

Steve Manning:  stephenm@ix.netcom.com
...Physical home: Metro D.C. area, USA
.....Virtual home:  http://www.stationwagon.com