just a quick question what is the best brake fluid to use dot 3 or dot 4?

any input welcomed

jon

Either can be used (and mixed) in the Fiero brake system, but for performance (fade resistance) go with DOT4.

DOT 5.1 if you can find it, otherwise DOT 4

http://en.wikipedia.org/wiki/DOT_5.1

http://www.raceshopper.com/...od_brake_fluid.shtml

Just don't confuse DOT 5.1 with DOT 5.

DOT 3, DOT 4, DOT 5.1 are all glycol-based fluids and are compatible with each other. The higher the DOT rating, the higher the boiling temperature.

DOT 5 is silicone based, and will react with any trace of glycol-based fluid in your system to form a destructive sludge. Only really for a brake system that's been completely taken apart and cleaned of all traces of glycol-based fluid. Even then, DOT 5 is hydrophobic (unlike the glycol-based brake fluids), so rather than allowing moisture to mix throughout the fluid, water can tend to collect in pockets and cause localized corrosion. DOT 5 is also more compressible than the glycol based fluids, so it gives a mushier brake pedal. Not something I'd recommend for most people...

thank you for the input - I think i will go with dot 4 to keep thing simple

jon

See cave, brake fluid.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)