Date: Fri, 25 Jun 1999 13:31:51 -0400
Reply-To: Dominique Cormann <kozmik@WAVE.HOME.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dominique Cormann <kozmik@WAVE.HOME.COM>
Subject: Re: DOT3 vs DOT4
In-Reply-To: <001201bebef4$389d8ea0$a3e1a9ce@fj6wx>
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On Fri, 25 Jun 1999 03:19:34 -0700
Coby Smolens <cobys@WELL.COM> wrote:
> It was I who posted the initial note about DOT3 & 4 being compatible. I
> think it's a case of all of us having a piece of the truth, but I find
> myself coming down on the side of safety.
>
Thats what I also know to be true...they are compatible.
> I believe Eric is right about the non-reciprocity issue (you can go from
> DOT3 to 4 and not the other way around), although it seems to me the bigger
> front pads and disks of the later van would act to stabilize temperature,
> thereby obviating the need for a more robust fluid.
>
I think it depends more on how and where you drive. I've seen DOT 3 and
DOT 4 oils boil.
> It is true that the DOT4 has a higher boiling point and anything we can do
> to eliminate the possibility of anyone's experience of the heart-in-mouth
> feeling you get when the pedal starts heading for the floor just when you
> need it the most (i.e.: On US 1 on the California coast, coming down the 15%
> hill at the north side of the detour past Fort Ross last year with a load of
> German mother-in-laws and aunts, wife, teenage girls, and baggage for a two
> week trip - a situation everyone's familiar with, right?), we should do.
> Just like we tell folks to fill the sump with 20w-50 instead of 10W-30...
Normally its supposed to work that way. But from listening to
experiences with friends who AutoX. I've noticed some odd things about
the two ratings.
Grassroots ( a popular magazine for autoX'ers ), did some articles on
the different oils.
They found that FORD HD DOT 3 brake fluid had a boiling point as higher
or higher then different premium dot 4 racing brake fluids!
They made the recommendation to use this stuff instead, since they found
no reason to use the expensive DOT 4's ( they were comparing racing
brake fluids, not just normal DOT 4 stuff ).
Down at my local Canadian tire they have DOT 3, dot 4, and DOT 3 FORD
APPROVED brake fluid. The difference? The ford approved stuff has the
highest boiling point! Go figure.
All I can say is that, from autoX experience, the ford stuff did
actually have a higher boiling point...why I can't say. I even talked to
some Ford mechanics I knew...they don't know why there cars need higher
brake fluid boiling temps...or at least they wouldn't tell me...perhaps
out of embarrasement since they always try to find some fault with the
V-dubs me and my friend own... ;-)
--
============================================================---------
Dominique Cormann Email:kozmik@wave.home.com
dcormann@uoguelph.ca Homepage: http://kozmik.guelph.on.ca
