Dot 3 brake fluid

[y_p_w]

Originally Posted By: Ken2
There might be a few brake systems with elastomers that do not tolerate the borate esters in the DOT4 & higher brake fluids. These borate esters that raise the boiling point also do absorb moisture faster than plain polyglycol ether DOT3 fluid. There are some DOT3 fluids with a higher than minimum boiling point, but I do not know of a concise reference list.

The DOT 3 standard makes no specification of what proportion of materials is used. It specifies compatibility with specific materials, a dry boiling point, a wet boiling point, and a maximum viscosity at 100 deg C. I would be very much possible for a manufacturer to produce a brake fluid that meets DOT 5.1 specs but label it as a DOT 3 fluid. Some of the heavy duty DOT fluids probably do contain higher amounts of borate esters. There's nothing about the standard that deals with how fast it absorbs moisture or how long it lasts in a brake system.

I wouldn't rely on a label saying that it's "DOT 3" to tell me that it will last longer in a brake system without a flush.

 

[y_p_w]

Originally Posted By: stchman
Originally Posted By: FetchFar
I noticed my 11 Camaro uses DOT3 and my 07 BMW 530 uses DOT4. You would think Chevy would specify 4 in a car that many use for track fun. ... What is the problem in using DOT4 in a car said to use DOT3 (backward compatibility an issue?)?


People get all hung up on the DOT 3 vs. DOT 4 brake fluid. DOT 3 and 4 are essentially the same fluid it is that DOT 4 has a slightly higher boiling point.

Here is a table of the boiling points of various brake fluids.

Code:


DOT 3 205 °C (401 °F) 140 °C (284 °F)

DOT 4 230 °C (446 °F) 155 °C (311 °F)

DOT 5 260 °C (500 °F) 180 °C (356 °F)

DOT 5.1 260 °C (500 °F) 180 °C (356 °F)


DOT 5 is a silicone base brake fluid whereas DOT 5.1 is higher temp version of DOT 4.

So a system that requires DOT 4 one can put DOT 3 with no worries unless they are doing a lot of track racing.

I noted that track racers often just use a heavy duty DOT 3 and change it before every race. Most of the ones I see with that designation say a dry boiling point of 450 deg F, although I thought I saw 500 deg F once.

 

[dailydriver]

Originally Posted By: y_p_w
Originally Posted By: FetchFar
I noticed my 11 Camaro uses DOT3 and my 07 BMW 530 uses DOT4. You would think Chevy would specify 4 in a car that many use for track fun. ... What is the problem in using DOT4 in a car said to use DOT3 (backward compatibility an issue?)?

None. One should be able to use DOT4 (or even DOT5.1) in a system that contained DOT3. They're all glycol based and mix readily.


^^^Yes, I think that GM is stating the DOT 3 is a minimum requirement, although I have never seen ANY brake fluid with a spec lower than a DOT 3, do/did they (ever) exist??

I ONLY use higher end, performance DOT 4 fluids in my systems (brake and clutch).

 

[dailydriver]

Originally Posted By: y_p_w
I noted that track racers often just use a heavy duty DOT 3 and change it before every race. Most of the ones I see with that designation say a dry boiling point of 450 deg F, although I thought I saw 500 deg F once.


Yes, the Ford/Motorcraft High performance DOT 3 is probably the fluid you are referencing.
It has a 500* F DRY boiling point, but is right at the DOT 3 minimum for the WET point.

 

[Subdued]

Originally Posted By: dailydriver
Originally Posted By: y_p_w
Originally Posted By: FetchFar
I noticed my 11 Camaro uses DOT3 and my 07 BMW 530 uses DOT4. You would think Chevy would specify 4 in a car that many use for track fun. ... What is the problem in using DOT4 in a car said to use DOT3 (backward compatibility an issue?)?

None. One should be able to use DOT4 (or even DOT5.1) in a system that contained DOT3. They're all glycol based and mix readily.


^^^Yes, I think that GM is stating the DOT 3 is a minimum requirement, although I have never seen ANY brake fluid with a spec lower than a DOT 3, do/did they (ever) exist??

I ONLY use higher end, performance DOT 4 fluids in my systems (brake and clutch).

According to brake fluid wiki there was a DOT2, which was apparently castor oil and alcohol based.

http://en.wikipedia.org/wiki/Brake_fluid

 

[MAHLE_Collector]

Originally Posted By: Garak
Just a point of interest for users here, the G37 specifies DOT 3. Infiniti/Nissan's OEM brake fluid up here is actually DOT 4, though. Go figure.

European Nissan specifies for DOT 4 or 3. Our Navara's brake booster and master cylinder is an Ate make, so I'm kind sure that is what they used to fil in the factory which is the typical yellowish colored. However if You are up to buy new genuine fluid from the dealer You will get a blue one in a blue capped bottle. I also think that must be the Ate Super Blue Racing(DOT 4) inside.
Ate used to sell 'avarage' blue DOT 3(Original Blue) but as I know it is no more avilable.


Boiling points for DOT 4:
'Dry' - 230°C at least
Wet - 155°C at least

All data from the canisters and Ate webpage.

I hope I could add some value in this topic.

 

[doitmyself]

I have virtually zilch technical expertise about brake fluids. But, for my circumstances (flatlands, low performance daily drivers) I have never seen the need to go with the "claimed better" DOT 4 fluid when all my vehicles have recommended DOT 3.

I place the alleged moisture performance characteristics of DOT 3 above the temperature characteristics of DOT 4. I have never noticed a performance problem with DOT 3 regarding temperature problems, but I am not sure I would recognize if there was a problem.

This often posted link from Stop Tech states the following: http://www.stoptech.com/technical-support/technical-white-papers/brake-fluid

- .....This does not mean that DOT 4 fluids are necessarily better than DOT 3 fluids.

- The real differentiating factor is that DOT 4 fluid should be changed more often than a DOT 3 fluid, because of the effects and rates of water absorption.

- Because the DOT 4 grade fluid typically contains a different chemical composition, compatibility of system components may be an issue.


Again, in my circumstances, I prefer DOT 3 over DOT 4. I don't see that DOT 4 is better in a situation that never requires the higher temperature performance. It would be like someone using Amsoil in a Honda daily driver with a 3,000Mi OCI because the Amsoil might have the potential to provide more protection "just in case".

 

[Garak]

Originally Posted By: MAHLE_Collector
European Nissan specifies for DOT 4 or 3.

Another thread mentioned how the U.S. government was cracking down on the Super Blue. I think it's still available up here; in any case, ATE fluid is not terribly hard to find up here, provided one stays away from Walmart and Canadian tire.

 

[jake88]

There is a good chance if you buy the OEM DOT 3 that you are getting DOW brake fluid - which is good stuff, if you are for any reason worried.

 

[stchman]

Originally Posted By: MAHLE_Collector
Originally Posted By: Garak
Just a point of interest for users here, the G37 specifies DOT 3. Infiniti/Nissan's OEM brake fluid up here is actually DOT 4, though. Go figure.

European Nissan specifies for DOT 4 or 3. Our Navara's brake booster and master cylinder is an Ate make, so I'm kind sure that is what they used to fil in the factory which is the typical yellowish colored. However if You are up to buy new genuine fluid from the dealer You will get a blue one in a blue capped bottle. I also think that must be the Ate Super Blue Racing(DOT 4) inside.
Ate used to sell 'avarage' blue DOT 3(Original Blue) but as I know it is no more avilable.


Boiling points for DOT 4:
'Dry' - 230°C at least
Wet - 155°C at least

All data from the canisters and Ate webpage.

I hope I could add some value in this topic.


You do know that the US Government has now banned ATE Super Blue brake fliud. Dumb if you ask me.

 

[Voltmaster]

DOT is a federal standard, I highly doubt there is much diffrence between diffrent ones.


Dot4 should be an "improoved" formula, so if your taking out all the fluid its also not a bad choice.

 

[MAHLE_Collector]

Originally Posted By: stchman

You do know that the US Government has now banned ATE Super Blue brake fliud. Dumb if you ask me.
Which is strange because it was sold for over a decade. I remember it was still available early this year but now reading articles and checking shops they state that the sale is discontinued due federal law.
Sorry guys but this is another American idiot-proof junk. 'For easier differentation from other type of vehicle fluids' Because the amber color is not easier to confuse with motor oil...
Anyhow who runs this oil and would like to keep some stock buy as fast as possible. I think it will disappear quickly from the distributors but i may be wrong.

 

[y_p_w]

Originally Posted By: doitmyself
I have virtually zilch technical expertise about brake fluids. But, for my circumstances (flatlands, low performance daily drivers) I have never seen the need to go with the "claimed better" DOT 4 fluid when all my vehicles have recommended DOT 3.

I place the alleged moisture performance characteristics of DOT 3 above the temperature characteristics of DOT 4. I have never noticed a performance problem with DOT 3 regarding temperature problems, but I am not sure I would recognize if there was a problem.

This often posted link from Stop Tech states the following: http://www.stoptech.com/technical-support/technical-white-papers/brake-fluid

- .....This does not mean that DOT 4 fluids are necessarily better than DOT 3 fluids.

- The real differentiating factor is that DOT 4 fluid should be changed more often than a DOT 3 fluid, because of the effects and rates of water absorption.

- Because the DOT 4 grade fluid typically contains a different chemical composition, compatibility of system components may be an issue.


Again, in my circumstances, I prefer DOT 3 over DOT 4. I don't see that DOT 4 is better in a situation that never requires the higher temperature performance. It would be like someone using Amsoil in a Honda daily driver with a 3,000Mi OCI because the Amsoil might have the potential to provide more protection "just in case".


These are merely standards. There is nothing to keep a manufacturer of fluid from creating a fluid that meets all the DOT 4 fluid standards and labeling it as DOT 3. Many DOT 3 fluids include several of the components that pretty much have to be in DOT 4 fluid to meet the requirements.

 

[dailydriver]

Originally Posted By: MAHLE_Collector
Originally Posted By: stchman

You do know that the US Government has now banned ATE Super Blue brake fliud. Dumb if you ask me.
Which is strange because it was sold for over a decade. I remember it was still available early this year but now reading articles and checking shops they state that the sale is discontinued due federal law.
Sorry guys but this is another American idiot-proof junk. 'For easier differentation from other type of vehicle fluids' Because the amber color is not easier to confuse with motor oil...
Anyhow who runs this oil and would like to keep some stock buy as fast as possible. I think it will disappear quickly from the distributors but i may be wrong.


Yes, but except for the ease/convenience of knowing when your new fluid is coming out of the bleeders, when switching between the Blue and Type 200, there is NO difference in the quality/performance/specs/etc. between the two, save for the pretty blue dye, correct?? (Or is there something else about the Blue I do not know/realize?)

 

[MAHLE_Collector]

Originally Posted By: dailydriver

Yes, but except for the ease/convenience of knowing when your new fluid is coming out of the bleeders, when switching between the Blue and Type 200, there is NO difference in the quality/performance/specs/etc. between the two, save for the pretty blue dye, correct?? (Or is there something else about the Blue I do not know/realize?)

You are probably right, they look like to have the exact same specs. Also anyone who ever does a brake fluid change will notice the difference between old and fresh oil.
Luckily most people here have their heads on the neck to use it, not only for not allowing the scarf to ride up....If You get what I mean.

 

[CharBaby]

Originally Posted By: redhat
I'd like to think so, some say otherwise.

I flushed out the brake system on my Accord with Wearever (AAP Brand) DOT3 and that was May. No problems yet.


AAP and Super Tech brake fluid is just about all I use. Over 20 years!

 

[y_p_w]

Originally Posted By: MAHLE_Collector
Originally Posted By: dailydriver

Yes, but except for the ease/convenience of knowing when your new fluid is coming out of the bleeders, when switching between the Blue and Type 200, there is NO difference in the quality/performance/specs/etc. between the two, save for the pretty blue dye, correct?? (Or is there something else about the Blue I do not know/realize?)

You are probably right, they look like to have the exact same specs. Also anyone who ever does a brake fluid change will notice the difference between old and fresh oil.
Luckily most people here have their heads on the neck to use it, not only for not allowing the scarf to ride up....If You get what I mean.

Brake fluid sold in the US is allowed to be anywhere from clear to amber. I'm wondering why some enterprising company doesn't just sell a combination of clear and heavily dyed fluids to achieve a similar goal.

And as far as I could tell, ATE never actually claimed that Super Blue was exactly the same (other than the dye) than one of their standard brake fluids. That was more or less assumed from the specs.

 

[dailydriver]

Originally Posted By: y_p_w
And as far as I could tell, ATE never actually claimed that Super Blue was exactly the same (other than the dye) than one of their standard brake fluids. That was more or less assumed from the specs.


I once spoke to one of their US based distribution tech people and they confirmed this (that they ARE exactly the same, save for the dye), but they could be wrong.