Dot 4 has a higher boiling point.  Could make a difference in down hill
situations.  In addition, the Castrol Dot 4 is a higher quality fluid more
resistant to absorbing moisture.  Besides leading to rust and corrosion is the
system, moisture will obviously lower the boiling point. Enough of it could
cause unexpected failure after a hard stop.  I had it happen to me in a 924.
Panic stop, later no brakes.  Bleed and refilled system, was okay again. Good
brake fluid is cheap insurance.

Dennis

-----Original Message-----
From:   Vanagon mailing list  On Behalf Of Chris Turner
Sent:   Saturday, August 30, 1997 2:35 AM
To:     Vanagon@GERRY.SDSC.EDU
Subject:        Re: DOT3 vs DOT4

In a message dated 97-08-28 11:58:25 EDT, richard@BALLY.COM writes:

<< Seems like there have been several e-mails about only using DOT4 in
Vanagon
 brake systems. The manual in my 1985 says to use DOT3 or DOT4. Anyone care
 to comment as I put DOT3 in mine. Did I screw up??? >>

no, you're fine..
there are not many cars that absolutely just HAVE to have DOT4, and the
Vanagon ain't one of them..
DOT3, DOT4, in the vanagon it makes no difference.

chris