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Old 30th March 2009, 08:25   #16
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Originally Posted by Mpower View Post
you have to be literally coming down a mountain with 5 people to experience fade in a normal car.
Sustained braking down hill in heavily loaded vehicles is the most likely situation for brake fade for most "normal" people.

but I've experienced fade on the street outside of those conditions, and frankly, the last time it happened, it scared the bejesus out of me so badly that after that, for a period of 10+ years, I stopped using brakes hard. I would back off the throttle early, and use the brakes gently, and just got very sloppy in my driving. I just could not trust brakes for my safety after that event. It was not until I started going to the track that I relearned to trust the brakes, and learned to use them hard, to stay in the throttle deep into the corners, use the brakes to rotate the car into the corner (trail braking).

the point is, brake fade is all too possible on the street, depending on how you drive. I could make an Innova's brake fade very quickly, even with no passengers. Its all about how you drive. if you are good and you come out of corners with a high exit speed, and you're hard on the throttle late into the next corner, and you brake hard and late for it, and repeat, the brakes of a vehicle like an innova can fade pretty quickly. A bad driver can also bring about the same result by braking too early and too hard then coasting through corners in a sloppy fashion, so even though his average speed won't be high, he'll be punishing the brakes.
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Old 30th March 2009, 09:54   #17
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The reduction of friction termed brake fade is caused when the temperature reaches the "kneepoint" on the temperature-friction curve. [All brake lining is cured under mechanical pressure following a heating & cooling curve, heating the friction material up to 450įF to "cure" (cross-link) the phenolic resin thermoset polymers: There is no melting of the binding resins, because phenolic resins are thermoset, not thermoplastic] In this form of fade, the brake pedal feels firm but there is reduced stopping ability. Fade can also be caused by the brake fluid boiling, with attendant release of compressible gases. In this type of fade, the brake pedal feels "spongy". This condition is worsened when there are contaminants in the fluid, such as water, which most types of brake fluids are prone to absorbing to varying degrees. For this reason brake fluid replacement is standard maintenance.

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After how many kms of spirited driving? you have to be literally coming down a mountain with 5 people to experience fade in a normal car.
Yup, it happened on a ghat section. And this happens only on the Innova. I have never experienced brake fade of any sort on the VTEC.

Will get the pads and the fluid checked.

Maybe instead of using DOT 5.1, i can get the stock fluid replaced on a regular basis. This might do the trick.


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Old 30th March 2009, 10:01   #18
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It is possible that what you are calling fade is not actually fade. In brake fade, the pedal remains firm. the pads lose friction on the disc. braking distances lengthen exponentially. Thats fade.
Thats confusing coz according to this, all symptoms are considered as brake fade.

The third form of brake fade is fluid fade. When this happens the brake pedal does become spongy, and sometimes you can push the pedal to the floor with little effect. It is caused by boiling brake fluid.

Brake fluid is hydroscopic, meaning it absorbs water from the air very easily. The more it absorbs, the further its boiling point drops, until it falls low enough to be boiled by heat from the brake. This creates gas bubbles in the brake lines and pressing the pedal simply compresses the gas without applying the brakes.

The cure is to change the brake fluid, using a replacement only from a sealed tin. Even an hourís exposure to humid air is too much.


Source - The knowledge: brake fade


Quote:
After how many kms of spirited driving? you have to be literally coming down a mountain with 5 people to experience fade in a normal car.
Yup, it happened during spirited driving on a ghat section.

And this happens only on the Innova. I have never experienced brake fade of any sort on the VTEC. Not even when i drove Wolf's car on track.

Maybe instead of using DOT 5.1, i can get the stock fluid replaced on a regular basis. This might do the trick.

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Old 27th April 2016, 17:26   #19
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Default Re: Anyone using DOT 5.1 brake fluid??

Brembo Dot 5.1 oil recently launched in India. Its Excellent available in 1 ltr and 500 Ml pack. Made in EU.

Very high grade and quality product currently just tried on my Mercedes W203 the brake feel had improved dramatically. Mine was a bit spongy before. it seems as though its a newer merc.

I have bought the oil from

https://www.facebook.com/unitedmotors91/
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Old 27th April 2016, 17:58   #20
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Default Anyone using DOT 5.1 brake fluid??

Quote:
Originally Posted by lillios View Post
Brembo Dot 5.1 oil recently launched in India. Its Excellent available in 1 ltr and 500 Ml pack. Made in EU.



Very high grade and quality product currently just tried on my Mercedes W203 the brake feel had improved dramatically. Mine was a bit spongy before. it seems as though its a newer merc.



I have bought the oil from



https://www.facebook.com/unitedmotors91/

Don't want to put a damper on your enthusiasm, but a different brake fluid can't be the reason for your pedal feeling less spongy. Liquid is liquid when it comes to its inability to be compressed. Unless it was under driving conditions as described before where you might be experience various aspect of fading and such.

If it felt spongy and now it doesn't it means most likely there was a bit of air trapped into your brake system. Most likely as the system got flushed and or refilled it also got rid of the air.

I hope you had a different then DOT5 liquid before as 5.1 is compatible with DOT 3 and 4 but not 5

The biggest thing with 5.1 is the higher boiling points. Not sure how you can quantify any other advantages such as it being a high grade product? Not sure what that means.

Please note that it really isn't an oil at oil. It's a glycol based product.

Jeroen

Last edited by Jeroen : 27th April 2016 at 18:01.
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Old 27th April 2016, 19:43   #21
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Default Re: Anyone using DOT 5.1 brake fluid??

Quote:
Originally Posted by Jeroen View Post
Don't want to put a damper on your enthusiasm, but a different brake fluid can't be the reason for your pedal feeling less spongy. Liquid is liquid when it comes to its inability to be compressed. Unless it was under driving conditions as described before where you might be experience various aspect of fading and such.

If it felt spongy and now it doesn't it means most likely there was a bit of air trapped into your brake system. Most likely as the system got flushed and or refilled it also got rid of the air.

I hope you had a different then DOT5 liquid before as 5.1 is compatible with DOT 3 and 4 but not 5

The biggest thing with 5.1 is the higher boiling points. Not sure how you can quantify any other advantages such as it being a high grade product? Not sure what that means.

Please note that it really isn't an oil at oil. It's a glycol based product.

Jeroen
Hello Jeroen

You are right must be the brake bleeding which has got rid of air in the lines.

But also I would bring to your notice that cars with ABS and TCS such high grade compatible oil does make a difference. And for long rides in this climate on highways braking frequently the high boiling point is huge advantage also for occasional track use.
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Old 27th April 2016, 21:52   #22
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Default Anyone using DOT 5.1 brake fluid??

Quote:
Originally Posted by lillios View Post
Hello Jeroen



You are right must be the brake bleeding which has got rid of air in the lines.



But also I would bring to your notice that cars with ABS and TCS such high grade compatible oil does make a difference. And for long rides in this climate on highways braking frequently the high boiling point is huge advantage also for occasional track use.

Why would ABS or TCS need 5.1? What would be better?
I would find it hard to believe that on modern cars you would experience brake fading due to the brake fluid starting to boil. Especially on motorways. You need prolonged and hard braking. Typically you might find yourself in such scenario in very hilly and or mountains going down hill.

Ambient temperature is a relative small factor. It's all about heat building up for a certain period. The dry boiling point of DOT 4 is 230oC. Whether you drive in 20 or 40oC is not going to make a lot of difference when it comes to heat building up and soaking into the brake liquid.

More importantly if you ask me is to refresh your Brake fluid regularly. I would take a fresh DOT 4 over a two year old DOT 5.1 any day!

Jeroen

Last edited by Jeroen : 27th April 2016 at 21:53.
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Old 2nd May 2016, 19:15   #23
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Default Re: Anyone using DOT 5.1 brake fluid??

Quote:
Originally Posted by Jeroen View Post
Why would ABS or TCS need 5.1? What would be better?
I would find it hard to believe that on modern cars you would experience brake fading due to the brake fluid starting to boil. Especially on motorways. You need prolonged and hard braking. Typically you might find yourself in such scenario in very hilly and or mountains going down hill.

Ambient temperature is a relative small factor. It's all about heat building up for a certain period. The dry boiling point of DOT 4 is 230oC. Whether you drive in 20 or 40oC is not going to make a lot of difference when it comes to heat building up and soaking into the brake liquid.

More importantly if you ask me is to refresh your Brake fluid regularly. I would take a fresh DOT 4 over a two year old DOT 5.1 any day!

Jeroen
Jeroen Your a master no arguments.

"Brembo Premium Brake Fluid DOT 5.1: with characteristics such as resistance to high temperatures and its superior viscosity value, it is recommended for high performance vehicles."

Brembo Premium brake fluids have a higher boiling point that exceeds the standard, thus offering superior resistance to the Vapour Lock and ensuring braking efficiency even at low temperatures. With high anti-corrosion properties and resistance to oxidation, Brembo brake fluid also allows for long-term unaltered chemical/physical characteristics of the fluid in operating circuit; therefore, preserving its integrity.

This was put on their site http://www.bremboparts.com/america/e...cs/brake-fluid

Also since my car is 2005 Merc its an Advantage to use such premium brake oil since it has moisture absorption quality which was mentioned in physical catalogue I have. This prevents calliper seals and brake lined form spoiling.

I was just praising Brembo as it's a quality product and making people aware of the new Dot 5.1 from them.
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Old 3rd May 2016, 13:30   #24
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Default Re: Anyone using DOT 5.1 brake fluid??

Quote:
Originally Posted by lillios View Post
Brembo Premium brake fluids have a higher boiling point that exceeds the standard, thus offering superior resistance to the Vapour Lock and ensuring braking efficiency even at low temperatures. With high anti-corrosion properties and resistance to oxidation, Brembo brake fluid also allows for long-term unaltered chemical/physical characteristics of the fluid in operating circuit; therefore, preserving its integrity.

its an Advantage to use such premium brake oil since it has moisture absorption quality which was mentioned in physical catalogue I have. This prevents calliper seals and brake lined form spoiling.
.
So, with this premium brake fluid, are you going to push out the normal brake fluid refresh time or not?

Jeroen
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Old 3rd May 2016, 13:35   #25
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Default Re: Anyone using DOT 5.1 brake fluid??

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Originally Posted by Jeroen View Post
So, with this premium brake fluid, are you going to push out the normal brake fluid refresh time or not?

Jeroen
Where refresh time is not mentioned Irrespective of which ever brake oil used. 2 years is the refresh period which I would follow to change brake oil.
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Old 3rd May 2016, 14:05   #26
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Default Re: Anyone using DOT 5.1 brake fluid??

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Originally Posted by lillios View Post
Where refresh time is not mentioned Irrespective of which ever brake oil used. 2 years is the refresh period which I would follow to change brake oil.
You should ask yourself why you are using two years in the first place perhaps! Even so, if using a premium brake fluid doesnt allow for longer use, what good would it be?

At least the suggestion is, it won't have a noticeable difference apparently.

It says:

Quote:
With high anti-corrosion properties and resistance to oxidation, Brembo brake fluid also allows for long-term unaltered chemical/physical characteristics of the fluid in operating circuit
and

Quote:
to use such premium brake oil since it has moisture absorption quality which was mentioned in physical catalogue I have. This prevents calliper seals and brake lined form spoiling
But not so much that you could leave it for a bit longer in the system I understand? Waste of money if you ask me then? The fading, unless you frequently power down very steep hills and mountains isnt really an issue either.

The brake fluid discussion is a bit like the lubrication oil discussion. It's mostly powered by clever marketing slogans, but not necessarily by any factual practical data.

Very few of us would bother to actually measure for instance the moisture content in our brake fluid. Its probably the easiest and the cheapest way to get a reasonable understanding of what the condition of your brake fluid is.

Test device cost just a few dollars:

http://www.ebay.com/bhp/brake-fluid-tester

As long as you dont mix Dot 5.0 into any of this, you won't be doing any harm. Whether you are doing anything particularly good, especially as you refresh every 2 years anyway, remains to be seen.

If buying the latest brake fluid, with some crafty slogans on the bottle, makes you feel happier, by all means go right ahead. I certainly have bought lots of stuff, in fact most of my stuff, without any rational thoughts, none whatsoever.

Jeroen
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Old 3rd May 2016, 15:14   #27
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Default Re: Anyone using DOT 5.1 brake fluid??

Quote:
Originally Posted by Jeroen View Post
You should ask yourself why you are using two years in the first place perhaps! Even so, if using a premium brake fluid doesnt allow for longer use, what good would it be?

At least the suggestion is, it won't have a noticeable difference apparently.

It says:



and



But not so much that you could leave it for a bit longer in the system I understand? Waste of money if you ask me then? The fading, unless you frequently power down very steep hills and mountains isnt really an issue either.

The brake fluid discussion is a bit like the lubrication oil discussion. It's mostly powered by clever marketing slogans, but not necessarily by any factual practical data.

Very few of us would bother to actually measure for instance the moisture content in our brake fluid. Its probably the easiest and the cheapest way to get a reasonable understanding of what the condition of your brake fluid is.

Test device cost just a few dollars:

http://www.ebay.com/bhp/brake-fluid-tester

As long as you dont mix Dot 5.0 into any of this, you won't be doing any harm. Whether you are doing anything particularly good, especially as you refresh every 2 years anyway, remains to be seen.

If buying the latest brake fluid, with some crafty slogans on the bottle, makes you feel happier, by all means go right ahead. I certainly have bought lots of stuff, in fact most of my stuff, without any rational thoughts, none whatsoever.

Jeroen
I have no Arguments with you. I just mentioned my personal opinion. Just because you have been previously buying stuff and they have not matched your expectations doesn't mean everything which is written is fake. Have you used Brembo Dot 5.1 oil yourself sir? if no pm me your address I would send you some then may be your opinion may change.

By the way I do own brake fluid tester as well as Autel 708 Maxi scan diagnostic tool as well as mityvac brake bleeder and tool to measure brake pad wear.
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Old 3rd May 2016, 18:44   #28
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Originally Posted by lillios View Post
I have no Arguments with you. I just mentioned my personal opinion. Just because you have been previously buying stuff and they have not matched your expectations doesn't mean everything which is written is fake. Have you used Brembo Dot 5.1 oil yourself sir? if no pm me your address I would send you some then may be your opinion may change.



By the way I do own brake fluid tester as well as Autel 708 Maxi scan diagnostic tool as well as mityvac brake bleeder and tool to measure brake pad wear.

It's not about the arguments being fake perse. It's about the lack of being able to factually verify that as an owner your are actually getting any tangible, practical benefits.

This product, going by its description should enable the owner to refresh less frequent? But is that true in practice and how to quantify and measure? Very difficult to come up with anything that would make sense, let alone make statistical significance. I currently own only five cars, so that is never enough to measure something like this.

When it comes to lub oil and brake fluid I buy the cheapest stuff that complies with the manufacturers recommended specifications. I have never seen real world test data that would suggest otherwise. In fact, when it comes to lub oil I have been part of real world testing to come to this conclusion. I've written about it in some other thread.

My experience with brake fluid is that on modern cars, even high performance heavy cars such as my Jaguar XJR I never experienced fading. Even barreling down the Rocky Mountains was no problem.

On most of my classic cars fading can be a problem when driving down steep mountains. I must confess to more then one close call with my Alfa Spider in the Eiffel and the Alps.

I check the moisture content twice a year and will flush the system as soon as it goes above 1% or two years, which ever comes first. I have not been able to correlate it to weather, ambient temperature, humidity, mileage or whatever. It just happens it seems. Or sometimes it doesn't.

Jeroen
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