As I understand it the "DOT" means Department of Transportation. The
"3, 4, 5" is a set of specifications that the break fluid has to meet in
order to be approved by the DOT. As far as I know the "4" or "5" is not
necessairly better than the 3, just different. The 3 may be better than the
5 for some applications. As far as actual use is concerned all I know is
that the manual says the break fluid must meet or exceed DOT 3 specs. As
long as you have that you are OK. Some fluids claim to be better than others
but I dont know about that.
     Castrol HAS however come out with a synthetic fluid that seems to be
good. Regular break fluid LOVES water and will absorb all it can get. This
is one of the BIG reasons why they say to change the fluid every couple of
years. The new Castrol claims to HATE water and will absorb little or none.
That alone will make it better whatever other benefits it has. It also
claims to be compatable with DOT 3 and can be mixed freely with it. Unless I
hear some discouraging words regarding it I am going to give it a try this
summer.
  -----Original Message-----
  From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]On Behalf Of
MtnGal
  Sent: Sat, April 03, 1999 5:26 AM
  To: vanagon@GERRY.VANAGON.COM
  Subject: Brake fluid DOT 3-4-5-?

  Could somebody please tell me about Brake Fluid.
  What the DOT 3-4-5-? pertains to?

MtnGal
  Bronze, 7 passenger 84 Vanagon GL [PPL-MVR]
  Today, I can cry because roses have thorns, or....I can
  celebrate that thorns have roses.

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