Brake fluid

What's the difference between dot 4 and dot 5? I mistakingly ordered dot 5 bel ray synthetic when my bike calls for dot 4. Should I swap it out or will it work ? :D:)

I guess tis the season for fluid changes. Assuming you saw this thread already. Ill add to it by saying that if I recall correctly, the Dot5 is more hygroscopic (thus - absorbing water quicker) then Dot 3/4, and would require more frequent changes to maintain consistent performance.

I go with the Dot3 (castrol)GT LMA or BelRay dot 4, both are cheap and available, but the LMA is good for those 3am insomniac visits to walmart :)

I saw a discussion that DOT 5 can be harmful to the rubber seals in some systems. Don't know if this is true or not.

DOT 5 is just fine if you completely drain the system DRY before adding it. Mixing 4 and 5 together will cause thickining and will ruin the seals on the actuator. I learned that lesson the hard way a while back. If you have mixed them FLUSH YOUR SYSTEM IMMEDIATELY!

Bonzai :)

I guess tis the season for fluid changes. Assuming you saw this thread already. Ill add to it by saying that if I recall correctly, the Dot5 is more hygroscopic (thus - absorbing water quicker) then Dot 3/4, and would require more frequent changes to maintain consistent performance.

I go with the Dot3 (castrol)GT LMA or BelRay dot 4, both are cheap and available, but the LMA is good for those 3am insomniac visits to walmart :)

You have that backwards actually. DOT5 is LESS hygroscopic. It was designed for the military so that it does not absorb water and can be used in a vehicle stored for long periods of time without getting contaminated by water.

I guess tis the season for fluid changes. Assuming you saw this thread already. Ill add to it by saying that if I recall correctly, the Dot5 is more hygroscopic (thus - absorbing water quicker) then Dot 3/4, and would require more frequent changes to maintain consistent performance.

I go with the Dot3 (castrol)GT LMA or BelRay dot 4, both are cheap and available, but the LMA is good for those 3am insomniac visits to walmart :D

You have that backwards actually. DOT5 is LESS hygroscopic. It was designed for the military so that it does not absorb water and can be used in a vehicle stored for long periods of time without getting contaminated by water.

Thanks :) I just know I have a sticky note on my brain to not exceed 4 for any purpose unless it was a new system altogether but I couldn't remember why.

I just know like oil, if you buy cheap - buy often :D

(no, no Rotella ramblings from me today :D )

Thanks for straightening this out guys :D

Ditto on the DOT5 is less hygroscopic. A drawback is that it is actually a compressible fluid, therefore creating a spongy feel in the brakes.

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