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I have always used Castrol DOT 4 in my brake and clutch systems with no problems.  Was shopping for some new containers to find that nobody seems to sell Castrol DOT 4 anywhere in the US.  I see Pentosin has a Super DOT 4 which looks very high quality.  

Anybody have other suggestions they have been successfully using - system is stock brake and clutch with stainless lines and CNC clutch slave.


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Here is a useful thread...

And some additional information and other fluids I considered:

Brake Fluid                      Dry Boiling Point   Wet Boiling Point     Price         
AP SUPER 600                           590°F                410°F                  $18.00/16.9oz
CASTROL SRF                            590°F                 518°F                  $69.99/33.8oz
NEO SUPER DOT 610               610°F                421°F                  $15.00/12oz
MOTUL RACING 600                593°F                420°F                  $15.00/16.9oz
MOTUL DOT 5.1                        509°F               365°F                  $6.50/16.9oz
ATE SUPER BLUE**                   536°F               392°F                  $11.99/33.8oz**
VALVOLINE SYNPOWER           503°F                343°F                 $4.97/16.9oz
ATE SL                                         500°F                329°F                 $7.95/16.9oz
CASTROL LMA                           450°F                311°F                 $3.50/16.9oz
AP 551                                        528°F                288°F                 $12.50/16.9oz
Ford C6AZ-19542-AA*              550°F               290°F                 $6.95/12oz*

* Ford Heavy Duty DOT 3 is very inexpensive and is popular among racers because of its excellent dry boiling point. Considered by many to be the best-kept secret in brake fluids. IT DOES ABSORB MOISTURE QUICKLY THOUGH. Recommended by Baer and Alcon. According to Hot Rods and Horsepower: "Ford Motor Company purchases Castrol SRF by the barrel, repackages it, and sells it as Ford Heavy Duty fluid to owners of heavy-duty trucks. Anyone may buy it from a Ford dealer under part number C6AZ-19542-AA." Although this rumor is often repeated on the 'Net', given the different specs between the two fluids, this assertion seems questionable at best.

** ATE Super Blue DOT 4 is even LESS expensive per ounce than the Ford Heavy Duty brake fluid and ABSORBS MOISTURE SLOWLY! And that’s why I chose it.  BUT, I don't think it's available anymore.  It seems the Feds didn't like that it was blue.  So buy the ATE 200, which is the same thing, but Amber in color.

Last edited by garth66

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