Are they pretty much all the same vs manufacture dot 3 (Toyota brand).
Thanks.
Thanks.
Dot 3 brake fluid
- Thread starter ARB1977
- Start date
- Status
YES
There are differences between DOT 3 brake fluids, but probably not enough for the average driver to care. DOT 3 specifies a minimum standard for dry and wet boiling points as well as compatibility with brake system materials.
There are some "heavy duty" brake fluids with extremely high dry boiling temperature but normal DOT 3 boiling temp when "wet". I understand that a lot of weekend racers will just use something like that and install fresh fluid just before a race so that wet boiling temp isn't an issue. Racers are constantly using the brakes, but I don't expect that the average person on the street is going to be braking that often.
Personally I think OEM brake fluid is oversold as being beneficial compared to any other brake fluid. It's likely just something that meets the DOT 3 spec and where suppliers can be changed if they provide a better price. For a daily driver I'd say just use any off the shelf DOT 4 fluid, or maybe a DOT 5.1 fluid if you're really paranoid. And have it changed every few years. I seem to recall that Toyota doesn't specify an interval to change brake fluid.
There are some "heavy duty" brake fluids with extremely high dry boiling temperature but normal DOT 3 boiling temp when "wet". I understand that a lot of weekend racers will just use something like that and install fresh fluid just before a race so that wet boiling temp isn't an issue. Racers are constantly using the brakes, but I don't expect that the average person on the street is going to be braking that often.
Personally I think OEM brake fluid is oversold as being beneficial compared to any other brake fluid. It's likely just something that meets the DOT 3 spec and where suppliers can be changed if they provide a better price. For a daily driver I'd say just use any off the shelf DOT 4 fluid, or maybe a DOT 5.1 fluid if you're really paranoid. And have it changed every few years. I seem to recall that Toyota doesn't specify an interval to change brake fluid.
They are all similar but some have higher dry/wet boiling point than others. If you bleed the brake system every 3-4 years and your driving doesn't involve hilly roads then it doesn't matter.
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?)?
Does anyone know of any data for the high temp DOT 3 vs standard DOT 3 fluids comparing rate of moisture absorption and seal compatibility/life? How do they achieve the high dry boiling point in the high temp DOT 3?
Last edited:
ATE used to offer their regular brake fluid in blue and also in gold. No difference in performance but you could tell if you made a complete flush by the color change.Don't know if anyone else did that. Wish someone cheaper did that. Just FYI, not directly on point. It seems most European cars specify reqular fluid changes, US suppliers focus more on low maintenance.
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.
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.
Originally Posted By: bmwjohn
ATE used to offer their regular brake fluid in blue and also in gold. No difference in performance but you could tell if you made a complete flush by the color change.Don't know if anyone else did that. Wish someone cheaper did that. Just FYI, not directly on point. It seems most European cars specify reqular fluid changes, US suppliers focus more on low maintenance.
Apparently they took the blue stuff off the market in the US because someone realized that the FMVSS 116 requirement for glycol-based brake fluid was that it must be anywhere from clear to amber. Silicone brake fluid is required to be dyed purple.
Quote:
http://www.gpo.gov/fdsys/pkg/CFR-2012-title49-vol6/xml/CFR-2012-title49-vol6-sec571-116.xml
S5.1.14 Fluid color. Brake fluid and hydraulic system mineral oil shall be of the color indicated:
DOT 3, DOT 4, and DOT 5.1 non-SBBF—colorless to amber.
DOT 5 SBBF—purple.
Hydraulic system mineral oil—green.
ATE used to offer their regular brake fluid in blue and also in gold. No difference in performance but you could tell if you made a complete flush by the color change.Don't know if anyone else did that. Wish someone cheaper did that. Just FYI, not directly on point. It seems most European cars specify reqular fluid changes, US suppliers focus more on low maintenance.
Apparently they took the blue stuff off the market in the US because someone realized that the FMVSS 116 requirement for glycol-based brake fluid was that it must be anywhere from clear to amber. Silicone brake fluid is required to be dyed purple.
Quote:
http://www.gpo.gov/fdsys/pkg/CFR-2012-title49-vol6/xml/CFR-2012-title49-vol6-sec571-116.xml
S5.1.14 Fluid color. Brake fluid and hydraulic system mineral oil shall be of the color indicated:
DOT 3, DOT 4, and DOT 5.1 non-SBBF—colorless to amber.
DOT 5 SBBF—purple.
Hydraulic system mineral oil—green.
Originally Posted By: edge10
Does anyone know of any data for the high temp DOT 3 vs standard DOT 3 fluids comparing rate of moisture absorption and seal compatibility/life? How do they achieve the high dry boiling point in the high temp DOT 3?
Probably some adjustment of the amount of borate esters. I think they can also engineer the process to achieve different polymers of the polyglycol esters.
http://iaspub.epa.gov/sor_internet/regis...alue=39434-94-1
Does anyone know of any data for the high temp DOT 3 vs standard DOT 3 fluids comparing rate of moisture absorption and seal compatibility/life? How do they achieve the high dry boiling point in the high temp DOT 3?
Probably some adjustment of the amount of borate esters. I think they can also engineer the process to achieve different polymers of the polyglycol esters.
http://iaspub.epa.gov/sor_internet/regis...alue=39434-94-1
There is no difference - there are only a handful of brake fluid manufacturers in the world, and OEMs rely on them for their fluids. The same manufacturers are making aftermarket products - so at the end of the day, some of the fluids are the same or similar enough that it does not matter.
European OEMs have a tendency to specify DOT 4 because of differences in the common drive cycle in Europe. DOT 4 should be flushed at least every 2 years to prevent the buildup of boric acid (a by-product of the reaction between borate ester and water).
European OEMs have a tendency to specify DOT 4 because of differences in the common drive cycle in Europe. DOT 4 should be flushed at least every 2 years to prevent the buildup of boric acid (a by-product of the reaction between borate ester and water).
Originally Posted By: jake88
European OEMs have a tendency to specify DOT 4 because of differences in the common drive cycle in Europe. DOT 4 should be flushed at least every 2 years to prevent the buildup of boric acid (a by-product of the reaction between borate ester and water).
That explains a lot, why BMW is big on 2-year brake fluid changes, and may explain why GM just specifies DOT3 and seems to never recommend brake fluid change.
European OEMs have a tendency to specify DOT 4 because of differences in the common drive cycle in Europe. DOT 4 should be flushed at least every 2 years to prevent the buildup of boric acid (a by-product of the reaction between borate ester and water).
That explains a lot, why BMW is big on 2-year brake fluid changes, and may explain why GM just specifies DOT3 and seems to never recommend brake fluid change.
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?)?
The Valvoline brake fluid I put in my Rainier is marked DOT 3 & 4.
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?)?
The Valvoline brake fluid I put in my Rainier is marked DOT 3 & 4.
I was told that alot of car companies use dot 3 over 4 because the higher the dot number 3 vs 4 vs 5.1 the faster they absorb water so they say it will last longer and require less maintainance with a lower number. Don't know how true this statement is.
I find that most generic replacement DOT3 is about the same, however, OEM DOT3 fluid varies. It really amazes me how slowly OEM Toyota fluid changes brown, and how GM turns brown quickly, they call their DOT3 "Delco Supreme"
DOT4 is made better than DOT3, and can replace it without any problem. Because of this, I use DOT4 in any car in my family, and all my family's cars call for DOT3.
DOT4 is made better than DOT3, and can replace it without any problem. Because of this, I use DOT4 in any car in my family, and all my family's cars call for DOT3.
Originally Posted By: vssjim
I was told that alot of car companies use dot 3 over 4 because the higher the dot number 3 vs 4 vs 5.1 the faster they absorb water so they say it will last longer and require less maintainance with a lower number. Don't know how true this statement is.
jake88 above mentioned that boric acid buildup is a problem with the higher DOT numbers.
I was told that alot of car companies use dot 3 over 4 because the higher the dot number 3 vs 4 vs 5.1 the faster they absorb water so they say it will last longer and require less maintainance with a lower number. Don't know how true this statement is.
jake88 above mentioned that boric acid buildup is a problem with the higher DOT numbers.
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.
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 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.
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.
- Status