Different of brake fluid?

[brakingdrift]

Wat is the different between dot 3,dot 4 and dot 5?

Anyone any idea?

Edited February 24, 2009 by brakingdrift
error typo

[ççãæˆæç¾]

Different boiling point.

[brakingdrift]

ok,my brake pump stated only use Dot 3 and 4 brake fluid.

which brake fluid should i choose?

Why?

many thanks......

[Raptor]

I would use DOT 5 fluids but they are meant for hard braking like when on the track. Brake fluids can boil when brakes are used heavily.

 

But if its only for road riding.. don't need to spend that much but then again its your money.

[brakingdrift]

noted.........

many thanks..

[eedwinn]

DOT 4 fluid can be used in place of DOT 3, but NEVER mix DOT 5 fluid with DOT 3 or 4. The difference between DOT 3 and DOT 4 is how well they resist to boiling.Temperature ratings for DOT 4 are higher than those of DOT 3.

 

DOT 5 fluids have a temperature rating like the DOT 3 and 4, but they are silicone based and unless your brake system is designed for DOT 5, do not use it. If I'm not wrong, most Harley Davidson use the DOT 5 fluid.

 

Silicone based DOT 5 fluids do not absorb water in the way that DOT 3 and 5 fluids do. Water contamination is what kills brake fluids and since DOT 5 fluid won't absorb moisture, it would seem that DOT 5 is the way to go. Unfortunately, water can get into the DOT 5 braking system and when it does, it forms droplets. if a droplet gets heated to the point of boiling, it will flash into steam and cause all sorts of nastiness that will result in a loss of braking or possibly locking up the brakes. It is very unlikely this will happen, but it can. Changing the brake fluid of DOT 5 is as important as the other systems.

 

The DOT 3 and 4 brake fluids are hydroscopic meaning they absorb fluid. As moisture content goes up, the resistance to boiling goes down. This is the reason why it is so important to change and flush brake fluid on a regular basis. It is a good idea to change the fluid at least once a year, maybe more if you do wet weather riding or use your brakes more severely than the average rider.

[zeke uchiha]

DOT 4 fluid can be used in place of DOT 3, but NEVER mix DOT 5 fluid with DOT 3 or 4. The difference between DOT 3 and DOT 4 is how well they resist to boiling.Temperature ratings for DOT 4 are higher than those of DOT 3.

 

DOT 5 fluids have a temperature rating like the DOT 3 and 4, but they are silicone based and unless your brake system is designed for DOT 5, do not use it. If I'm not wrong, most Harley Davidson use the DOT 5 fluid.

 

Silicone based DOT 5 fluids do not absorb water in the way that DOT 3 and 5 fluids do. Water contamination is what kills brake fluids and since DOT 5 fluid won't absorb moisture, it would seem that DOT 5 is the way to go. Unfortunately, water can get into the DOT 5 braking system and when it does, it forms droplets. if a droplet gets heated to the point of boiling, it will flash into steam and cause all sorts of nastiness that will result in a loss of braking or possibly locking up the brakes. It is very unlikely this will happen, but it can. Changing the brake fluid of DOT 5 is as important as the other systems.

 

The DOT 3 and 4 brake fluids are hydroscopic meaning they absorb fluid. As moisture content goes up, the resistance to boiling goes down. This is the reason why it is so important to change and flush brake fluid on a regular basis. It is a good idea to change the fluid at least once a year, maybe more if you do wet weather riding or use your brakes more severely than the average rider.

 

Its a gd piece of info bro...

 

Learned something...Thanks

[hachi]

DOT 5.1 higher wet and dry boiling point. remember brake oil is the weakest link in braking system and crap brake pads,hose,master pump....etc can withstand more than 300c....Old and lousy brake oil.....If thy boil at 100c and while you are riding downhill..Good luck..change them every 1 or 2 years.....When I used to tour and track I change them every 6 months with DOT5.1.

Now for transport only change them yearly will be good enough.....

[Snoek]

DOT 4 fluid can be used in place of DOT 3, but NEVER mix DOT 5 fluid with DOT 3 or 4. The difference between DOT 3 and DOT 4 is how well they resist to boiling.Temperature ratings for DOT 4 are higher than those of DOT 3.

 

DOT 5 fluids have a temperature rating like the DOT 3 and 4, but they are silicone based and unless your brake system is designed for DOT 5, do not use it. If I'm not wrong, most Harley Davidson use the DOT 5 fluid.

 

Silicone based DOT 5 fluids do not absorb water in the way that DOT 3 and 5 fluids do. Water contamination is what kills brake fluids and since DOT 5 fluid won't absorb moisture, it would seem that DOT 5 is the way to go. Unfortunately, water can get into the DOT 5 braking system and when it does, it forms droplets. if a droplet gets heated to the point of boiling, it will flash into steam and cause all sorts of nastiness that will result in a loss of braking or possibly locking up the brakes. It is very unlikely this will happen, but it can. Changing the brake fluid of DOT 5 is as important as the other systems.

 

The DOT 3 and 4 brake fluids are hydroscopic meaning they absorb fluid. As moisture content goes up, the resistance to boiling goes down. This is the reason why it is so important to change and flush brake fluid on a regular basis. It is a good idea to change the fluid at least once a year, maybe more if you do wet weather riding or use your brakes more severely than the average rider.

 

good info! thx