Flush brake fluid

[BerkTechnology]

Speaking from personal experience.....

We used to bleed brakes after every session with our previous braking system. We literally went through a gallon of Motul brake fluid over a weekend. Since we upgraded the brakes to Performance Friction calipers & pads we don't have to worry about fluid fade anymore but we did get very familiar with different fluids in the process.

Castrol SRF is very good stuff. They are the champs at wet boiling points and are middle of the road for dry boiling points..... but we don't use it. Here is why...

With SRF once you boil the fluid it never quite recovers as well as some of the other options. If you experience fluid fade in the middle of the race or track session on SRF you'll have to baby it for at least a few laps. Once the fluid does recover, you essentially now have the same performance that a $3/bottle of brake fluid would give you.

We've been using Motul 660 for the past few years as it is one of the top performers in both wet & dry boiling points and has great recovery characteristics as well.

ATE Blue & Type200 = I guess you can't beat the price. Performance is ok.
Motul 600 = a little pricey for the performance. Good fluid but a pretty big difference compared to 660.
Motul 660 = excellent all around fluid.
AP PRF660 = I swear this is exactly the same as Motul 660. Just a different label.
Brembo LCF = good fluid. About the same as the Motul 600.
Neo Synthetics = good fluid but not worth the money. Costs a lot more than 660 for the same performance.
Elf something? = don't remember.

[BerkTechnology]

I want to try the Project Mu G4 335! Same price as the other premium fluids (~$30/L) but stellar performance.


ARRANGED BY DRY BOILING POINT(some prices from my 2010 list and some are updated, check with your favorite supplier, and look for case prices so you can change it often):

DRY:401F -- WET:284F --- DOT3 MINIMUM (GLYCOL BASE)
DRY:446F -- WET:311F --- DOT4 MINIMUM (GLYCOL BASE)
DRY:500F -- WET:356F --- DOT5 MINIMUM (SILICONE BASE)
DRY:500F -- WET:356F --- DOT5.1 MINIMUM (GLYCOL BASE)
DRY:500F -- WET:???F --- FORD HEAVY DUTY DOT 3 PM-1C (new since 2006)
DRY:527F -- WET:302F --- AP RACING 551 ($12.799/0.5L OR 16.9 OZ)
DRY:527F -- WET:347F --- VALVOLINE SYNPOWER DOT3 & DOT4
DRY:536F -- WET:388F --- ATE SUPERBLUE/TYP200 ($13.99/1L)
DRY:550F -- WET:284F --- FORD HEAVY DUTY DOT 3 PM-1 (pre 2006) ($4/12 OZ)
DRY:570F -- WET:284F --- WILWOOD 570 ($7.95/12 OZ)
DRY:570F -- WET:284F --- PERFORMANCE Friction Z rated ($6.27/16 OZ)
DRY:572F -- WET:410F --- AP RACING 600 ($19.95/0.5L OR 16.9 OZ)
DRY:590F -- WET:???F --- TILTON TBR-1 ($11.95/0.25L) (new since 2006)
DRY:590F -- WET:518F --- CASTROL SRF ($74.99/1.0L 0R 33.8 OZ)
DRY:593F -- WET:421F --- MOTUL RBF 600 ($15.99/0.5L OR 16.9 OZ)
DRY:601F -- WET:399F --- BREMBO LCF 600 PLUS ($19.95/0.5L OR 16.9 OZ)
DRY:608F -- WET:390F --- AP RACING PRF660 ($29.95/0.5L OR 16.9 OZ)
DRY:610F -- WET:421F --- NEO SYNTHETICS SUPER DOT 610 ($11.95/12 OZ)
DRY:613F -- WET:424F --- ENDLESS RF-650 ($33.00/0.5L OR 16.9 OZ)
DRY:617F -- WET:399F --- MOTUL RBF 660 ($28.99/0.5L OR 16.9 OZ)
DRY:617F -- WET:383F --- PFC RH665($28.99/0.5L OR 16.9 OZ)
DRY:622F -- WET:???F --- TILTON TSR-1 ($17.95/0.25L) (new since 2006)
DRY:626F -- WET:???F --- FERODO FSF050 Super Race Brake Fluid ($39.99/0.5L OR 16.9 OZ)
DRY:626F -- WET:417F --- WILWOOD EXP 600 ($18.99/0.5L 16.9 OZ)
DRY:635F -- WET:???F --- BREMBO HTC 64T ($32.00/0.5L 16.9 OZ)
DRY:635F -- WET:430F --- PROJECT MU G/FOUR 335 ($45.00/1.0L 33.8 OZ)
DRY:683F -- WET:439F --- PROSPEED RS683 ($39.99/0.5L OR 16.9 OZ)

ARRANGED BY WET BOILING POINT:

DRY:500F -- WET:???F --- FORD HEAVY DUTY DOT 3 PM-1C (new since 2006)
DRY:590F -- WET:???F --- TILTON TBR-1 ($11.95/0.25L) (new since 2006)
DRY:622F -- WET:???F --- TILTON TSR-1 ($17.95/0.25L) (new since 2006)
DRY:626F -- WET:???F --- FERODO FSF050 Super Race Brake Fluid (new since 2009)
DRY:635F -- WET:???F --- BREMBO HTC 64T
DRY:401F -- WET:284F --- DOT3 MINIMUM
DRY:570F -- WET:284F --- WILWOOD 570
DRY:570F -- WET:284F --- PERFORMANCE Friction Z rated
DRY:550F -- WET:284F --- FORD HEAVY DUTY DOT 3
DRY:527F -- WET:302F --- AP RACING 551
DRY:446F -- WET:311F --- DOT4 MINIMUM
DRY:527F -- WET:347F --- VALVOLINE SYNPOWER DOT3 & DOT4
DRY:500F -- WET:356F --- DOT5.1 MINIMUM (GLYCOL BASE)
DRY:500F -- WET:356F --- DOT5 MINIMUM (SILICONE BASE)
DRY:617F -- WET:383F --- PFC RH665 (new since 2011)
DRY:536F -- WET:388F --- ATE SUPERBLUE/TYP200
DRY:608F -- WET:390F --- AP RACING PRF660
DRY:601F -- WET:399F --- BREMBO LCF 600 PLUS
DRY:617F -- WET:399F --- MOTUL RBF 660
DRY:572F -- WET:410F --- AP RACING 600
DRY:626F -- WET:417F --- WILWOOD EXP 600
DRY:593F -- WET:421F --- MOTUL RBF 600
DRY:610F -- WET:421F --- NEO SYNTHETICS SUPER DOT 610
DRY:613F -- WET:424F --- ENDLESS RF-650
DRY:635F -- WET:430F --- PROJECT MU G/FOUR 335
DRY:683F -- WET:439F --- PROSPEED RS683 (new since 2010)
DRY:590F -- WET:518F --- CASTROL SRF

[Wings0fRed]

Nice data, is that your own personal bookkeeping or was that something you found online?

[HP Autosport]

Originally Posted by Scuderia000

I need to upgrade my brake fluid for a track session so I will be flushing out the old fluid. I have never done this before so I would like to confirm my plans before I screw something up. (Brakes are kind of improtant and I want them to work.) I plan to use Castrol SRF so I don't have to worry about flushing or bleeding the fluid after each event. Since the existing fluid and the Castrol SRF are the same/similar color (I assume), I plan to start flushing with ATE Super Blue to get a different color in the lines. Then flush with Castrol SRF until the ATE Super Blue is flushed out. I read that there is some brake fluid for the traction control system that requires a computer to flush out this fluid. I definitely won't be doing that, so that makes me wonder if that remaining fluid in the traction control system will mix with the Castrol SRF and reduce its effectiveness or boil during the track session even if it doesn't mix with the Castrol fluid. Also, should I flush the clutch fluid to prevent the old fluid from mixing with the new fluid in the master clyinder? I'll be using the Motive pressure bleeder at 10 psi. Please let me know if I should do something different or if I'm forgetting something. Thanks!!

Here is all the info you need on SRF:

Race Proven - Ultimate Racing Brake Fluid!
CASTROL SRF Racing Brake Fluid is an ultra high performance product formulated specifically to satisfy the ever increasing stresses placed upon the braking systems used in international motorsport. The exceptional performance of Castrol SRF is due to a novel silicon ester technology pioneered by Castrol and unique to the extent that it has been granted patent-protection in numerous countries throughout the world.

Castrol SRF Properties

Exceptionally high dry boiling point 590ºF (Wet 518ºF)
Superior anti-vapor lock properties
Safe for all non-mineral oil-based disc and drum brake systems
Exclusive European formula!
Exceeds SAE 1703, ISO 4925, JIS K2233, FMVSS No. 116 DOT3 and DOT 4

Castrol SRF Brake Fluid Technical Information
Castrol SRF Racing Brake Fluid is an ultra high performance product formulated specifically to satisfy the ever increasing stresses placed upon the braking systems used in international motorsport. The exceptional performance of Castrol SRF is due to a novel silicon ester technology pioneered by Castrol and unique to the extent that it has been granted patent-protection in numerous countries throughout the world.

Castrol SRF evolved as a direct result of Castrol's ongoing Research and Development program for brake fluids which identified this silicon ester technology as providing considerable performance benefits when compared with conventional glycol ether borate ester fluids.

Following exhaustive laboratory tests at Castrol's International Technology Centre in the UK, the final formulation for Castrol SRF was subjected to an extensive road-test programme on the Gross Glockner and Stelvio passes high in the Austrian and Italian Alps. It then underwent an independent track test program conducted by a famous Formula One racing team. Their assessment was that "Castrol SRF is the best racing brake fluid we have ever used."

Subsequently, Castrol SRF was offered to top flight racing and rally teams throughout the world including most of the Formula One teams, the all-conquering Jaguar and Mercedes -Benz sports car teams and the Audi, Nissan and Toyota rally teams. Enthusiastic recommendation by these experts soon created an immense interest in Castrol SRF throughout the whole spectrum of national and international motorsport. Today, Castrol SRF is regarded by the international motorsport community as being without equal and it is chosen not only by factory-supported teams but by private competitors throughout the world.

All conventional brake fluids used in cars and motor cycles are hygroscopic, that is, they absorb water from their surroundings. Strange though it may seem, the flexible hoses incorporated in braking systems are permeable to water and in time enough, water can find its way into the system via the hoses, and seriously affect the brake fluid's performance. This water reduces the boiling point of the fluid (ie, it lowers the temperature at which gas bubbles begin to form). When these bubbles form, they turn a virtually incompressible liquid into a mixture of gas and liquid which can be compressed quite considerably, thus severely reducing the efficiency of the brakes. In this situation, a driver finds that the brakes feel spongy. Brake-pedal travel will increase and it may be necessary to 'pump' the pedal to get the brakes to function effectively. However, when the brake fluid reaches a temperature at which the water in the fluid causes gas to be produced, which is equal to the volume swept by the piston in the rake master-cylinder, vapor-lock occurs and the brakes become inoperative. When this happens, the first indication the driver has that something is wrong is when he applies the brakes. The pedal goes down to the floor and the car carries on at undiminished - and possibly fatal speed.

The silicon ester technology in Castrol SRF addresses this problem in two ways. Firstly, Castrol SRF is less hygroscopic than conventional brake fluids - it absorbs less water in a given time. Secondly, unlike conventional glycol ether fluids, Castrol SRF reacts chemically with the absorbed water to reduce its adverse effects, thus preventing the fluid's high temperature performance and safety margins from deteriorating as rapidly as they would otherwise do.

Castrol SRF exceeds the US Federal Standards FMVSS 116 DOT 3 and DOT 4, ISO 4925, JIS K2233 and current SAE J1703 and is miscible with all conventional brake fluids conforming to these standards. However, mixing Castrol SRF and conventional brake fluids will reduce the benefits of Castrol SRF. It is strongly recommended that conventional brake fluid be drained from the system before flushing and refilling with Castrol SRF.

The wet boiling point of Castrol SRF, 270 C, is vastly superior to the minimum requirement of 155 C demanded by the current US DOT 4 specification. The product's typical dry boiling point of 310 C is likewise outstanding. This ability to withstand temperatures in excess of 300 C, and its superior resistance to the effects of absorbed water, have established Castrol SRF as the world's premier fluid for the hydraulic brakes used in all forms of motorsport.

http://www.1addicts.com/forums/showthread.php?t=589691

[EAS]

We would have to agree with Berk on this one; Motul is the way to go in our opinion and been very good in our own track experiences as well.

[HP Autosport]

As soon as you open up a bottle of conventional brake fluids it starts to absorb water right away - It's just the nature of the product.

You will not likely see the dry boiling point as advertised. You will want a product with both high and dry boiling point or flush your system out just before the next event. And if you are doing ~10 events a year, the Castrol SRF is a much better deal, as you not need to flush it each time.

[EAS]

Except for this reason that Berk Technology previously posted:

Originally Posted by BerkTechnology

Castrol SRF is very good stuff. They are the champs at wet boiling points and are middle of the road for dry boiling points..... but we don't use it. Here is why...

With SRF once you boil the fluid it never quite recovers as well as some of the other options. If you experience fluid fade in the middle of the race or track session on SRF you'll have to baby it for at least a few laps. Once the fluid does recover, you essentially now have the same performance that a $3/bottle of brake fluid would give you.

We've been using Motul 660 for the past few years as it is one of the top performers in both wet & dry boiling points and has great recovery characteristics as well.

[HP Autosport]

Originally Posted by david @ eas

Except for this reason that Berk Technology previously posted:

We not only competed in Redline Time Attack, but have been running track events since 2007 with a similar chassis 335i, not once did we experience such a thing with the Castrol SRF with Stoptech Trophy and Hawk DTC-series pads.

Any brake fluid once boiled air bubbles are introduced in the system and they turn a virtually incompressible liquid into a mixture of gas and liquid which can be compressed. Doesn't matter of you have $3 fluid or $80 fluid, you will need to flush it out.

I remember Berk running the Rotora setup and had many problems with overheating the brakes and fluids. Perhaps they were faulting the SRF fluid in this case, but the issue really was else where - Rotora Brakes

Quote from Berk:

"We used to bleed brakes after every session with our previous braking system. We literally went through a gallon of Motul brake fluid over a weekend. Since we upgraded the brakes to Performance Friction calipers & pads we don't have to worry about fluid fade anymore..."

I am sure if they were to use the SRF now, they will not experience the same issues.

[BerkTechnology]

We went through a gallon of brake fluid the at the Redline Time Attack season opener but the lack of ducting was mostly to blame. We built a new splitter setup for that day and I did not have time to incorporate the brake duct openings into the front bumper.

We ran on the Rotora's for the whole season after that even completing our "Super Sessions" in Time Attack which were 5 lap sprint races on the same brakes but with the brake ducts & TiSpeed titanium backing plates installed and they held up well enough through all of that abuse.

On that particular day we were also running the fastest times of the day.

Faster times = deeper & harder into the braking zones.

Here were the results of the 1 gallon brake fluid day. 1st place and a new Redline Time Attack record. I think we bummed a litre off every team in the pits that day!

http://www.redlinetrackevents.com/wp...ow_Results.pdf

[EAS]

If Berk Technology were running SRF that day it would have been much worse. They were bleeding after every single outing and fresh SRF would have preformed far worse than Motul 660. Motul 600 would have even been marginally better than SRF in those conditions since the fluid was fresh every time the car went out.

Here's some more about Berk:

http://www.motoiq.com/magazine_artic...mpionship.aspx

[HP Autosport]

Originally Posted by david @ eas

If Berk Technology were running SRF that day it would have been much worse. They were bleeding after every single outing and fresh SRF would have preformed far worse than Motul 660. Motul 600 would have even been marginally better than SRF in those conditions since the fluid was fresh every time the car went out.

Here's some more about Berk:

http://www.motoiq.com/magazine_artic...mpionship.aspx

Could be because Berk mix the two and reduce the benefit of the SRF:

"Castrol SRF exceeds the US Federal Standards FMVSS 116 DOT 3 and DOT 4, ISO 4925, JIS K2233 and current SAE J1703 and is miscible with all conventional brake fluids conforming to these standards. However, mixing Castrol SRF and conventional brake fluids will reduce the benefits of Castrol SRF. It is strongly recommended that conventional brake fluid be drained from the system before flushing and refilling with Castrol SRF."

As far as most people are concerned here, unless they are flushing their brake all the time, wet boiling point numbers are more important than dry.

Berk's finding is isolated plus the constant overheating issues with the Rotora brakes one can't really drawn a conclusion that Motul600 is better than SRF in this case.

As I have said above, get the SRF back on the car with Performance Friction Brakes and there will be no issues.

[BerkTechnology]

They're all good fluids. As long as you stick to the top tier stuff you'll be okay. I'm going to try out the Project Mu fluid the next time we need to buy fluid. Specs look awesome on paper and it's actually less expensive per/L than the Motul 660 and SRF.

Project Mu = $45/L
Motul 660 = $57.98/L
Castraol SRF = $74.99/L

[mbintx]

I'm a big fan of Motul (use in religiously in my track-prepped Miata), and am thinking of swapping brake fluid from OEM to Motul in the 135i for it's first-ever track day.
Reading through this thread it's not clear how much new brake fluid I need on hand for a complete flush. Is it one liter?

Also, no speedy vac for me. I'll do the old skool, "one person pumps the pedal while the other bleeds the brakes" method. I assume on the Bimmer I can use the most remote caliper to pump out the bulk of the old fluid, then work around the horn to catch the other individual lines.

Thanks.

[germ]

Did the brake fluid service today. My experience, in the hope it helps somebody:

1. I could not figure out how you can possibly do this without removing the wheels (as somebody posted). Not a big deal, you just need a jack, torque wrench, and 17 mm deep socket.

2. First step was removing the old fluid with a turkey baster. I could not figure out how to remove the "filter insert" in the brake fluid reservoir, so I left it in place and removed as much fluid as I could

3. The bleed valve is 11mm. Be carful not to strip the bolts! In one of the wheels, the bolt was already damaged (from the stealer, I guess). Remember, the screw is on the opposite side, so it turns the other way.

4. I used the popular pressure bleeder from Amazon, set at 15 psi, and ATE fluid. It's a pity you can only buy yellow, which leads to waste. The bleeding is slow, be patient. This was my first time, and it took a couple of hours.

4. To collect the old brake fluid you need ~1ft 1/4" ID PVC tubing, available in any hardware store.

5. I used almost all of 2 liter ATE bottles. If I knew how much fluid to bleed, I could probably save a lot of it.

The whole procedure is really easy, but somewhat messy as you need to deal with small spills etc. I wonder how much the stealer charges. I probably saved already even if I had to buy the bleeder and the jack.