whats the differents between brake fluids

[deathlucky]

what is the differennts between 3 dot 4 dot 5 dot and 5.1 dot

fluid what one is the best and for what reason?
what can be mixed with what?
do i need different parts for different fuilds?
why isnt this in FAQ?

thank you

[The Buddha]

3 and 4 are petro based. 5.1 is synthetic petro based. they all take on water and urn brown and they all eat paint. You can mix all of them - 3, 4, 5.1.
Dot % is entirely different. Its silicone based, its deep ble in color, has no affinity for water and does not eat paint. But to swicth to it, you have to evacuate the entire system, flush it and then put it in and bleed it. Worth it IMHO ... but some very very old school bikes need the petro base to keep the rubber soft. So silicone is bad for that.
Cool.
Srinath.

[annguyen1981]

D - I - F - E - R - E - N - C - E



j/k

[ducati_nolan]

Dot 3 and dot 4 are simmilar and I've seen brake fluid that claims that it's dot 3 and dot 4, or meets the requirements of both. I think that 4 has pretty much replaced 3 but I don't know if they are interchangable. I think the GS calls for dot 4 for so use that. Dot 5 is a silicone based fluid that definately isn't interchangable with 3 or 4 and if you decide to use it, you have to flush all the old fluid out of your system.

The claimed advantage of dot 5 is that it dosen't adsorb water. Dot 3 and 4 will adsorb some water out of the air over time and allow the boiling point to increase and corosion to form, thats why you're supposed to change it every 2 years. But with dot 5 if water dose get in there it will collect in the bottom of your resovour or caliper, and it's difficult to get out, and can also cause corrosion and other problems.

I don't think dot 5 is worth the hassle for it's claimed benifiits, just use what the manual calls for, change it every two years, and you shouldn't have any problems 
later 

[deathlucky]

ok i will stick with 4 whne i blead my brakes i put dot 4 in what was yellow and when the shop put the ss line on they put blue fluid in (i know this because i walked in to the workshop and watched them)

[ducati_nolan]

If the shop put the blue stuff in there just stick with it. Like I said it isn't interchangable and since the shop already flushed out your system and put in the dot 5, just stick with it, it isn't worth the hassle to flush it out. If you've already mixed them, then you'll have to flush it out anyways and then take your pick.
ride safe 

[deathlucky]

they put blue stuff in it and i put yellow stuff in last weekend when i broke my caliper and had to put in back together

[ducati_nolan]

When you broke your caliper, did you drain all of your fluid out of the resovour, line and caliper? if so you should probally be okay, since you more or less flushed out the system before you put the dot 4 in there.

If you mixed them, you should flush it all out and replace it with either 4 or 5 but not both. srinath mentioned that the 5 dosen't eat paint, so that's an advantage, but I don't think you'll se a performance difference between the two.

You may want to look in your resovour to see if you see any blue stuff left over, and bleed the brakes to see if any blue comes out. If so, flush it out. I'm not sure exactly how critical it is if they mix, but it can't be a good thing and you'd hate your brakes to get screwed up at a critical moment 
good luck 

[Altephor]

D - I - F - E - R - E - N - C - E



j/k

....you spelled difference wrong.

[wyiel]

D - I - F - E - R - E - N - C - E



j/k

....you spelled difference wrong.

+1

[deathlucky]

sucked in you yryed being a smart ass and you got cut
thanks for the help everyone

[annguyen1981]

....you spelled difference wrong.

DAMN!

It took 2 hours and 15 minutes for someone to notice that.  What the hell is wrong with you people.

[annguyen1981]

sucked in you yryed being a smart ass and you got cut
thanks for the help everyone

I tried to be funny and spell it incorrectly, but it took too long for someone to notice it.  By then, I was asleep.

Oh well, I'll have fun another day.

[deathlucky]

sucked in you yryed being a smart ass and you got cut
thanks for the help everyone

I tried to be funny and spell it incorrectly, but it took too long for someone to notice it.  By then, I was asleep.

Oh well, I'll have fun another day.

oh yer nice cover story

[pantablo]

....you spelled difference wrong.

DAMN!

It took 2 hours and 15 minutes for someone to notice that. What the hell is wrong with you people.

you mean it actually took 2 hrs and 15 min for someone to care enough or have enough energy to bother telling you as such..instead of just smirking smugly at your incompetence.

[annguyen1981]

you mean it actually took 2 hrs and 15 min for someone to care enough or have enough energy to bother telling you as such..instead of just smirking smugly at your incompetence.

Well, I though someone would be like, "WTF!  He has the stupidity to correct someone's spelling, and he didn't even spell it correctly himslef?!!?!?"

[MarkusN]

As for your initial question: increasing DOT nos will tolerate higher temperatures before they begin to boil (which will in turn lead to fading).

Basically the higher the DOT no, the harder you can be on your brakes before they give warning signs or crap out altogether.

[LimaXray]

I use AP Racing brake fluid in my bike and my car.  I believe it is DOT4, but it has a higher boiling point than regular brake fluid.  This means you're less likely to experience vapor lock (when the brake fluid gets so hot it boils producing vapor in the brake line resulting in the brakes going very very soft).  I have never had this issue with my bike, but I have experienced vapor lock in my car from spirited driving, and let me tell you, it's not fun.  

You can find it online, at various stores or even eBay.