dmtnt

SRF eats the seals in our braking systems - true or false?

Mallett says yes, LG says no, DRM sells it, some big brake vendors won't even warranty their kits unless you use SRF. I've been using it with no problems, I know John Shiels uses it. Let's settle this rumor once and for all!

AU N EGL

I use it and love it.

I use to use that super blue / gold stuff. I boild it tooo many times, had major brake fade and even brake falure with it. I was bleeding and bleeding my brakes compleatly replacing my brake fluid, which you must do if your evern boil brake fluid.

Then I switched to Castrol SRF. Yes it was $65 / liter and I bought 3 litters. It took a litter to fully bleed out the old blue and replace with SRF. Then almost another litter to fill my brake system and bleed a bit more after driving a weekend on the track or two.

Now I have NO or minimal brake fade, Good solid peddle feel, I do check or do a minimal bleed before each weekend onthe track. No problems.

I also use Wilwood H pads now.

I wont use anything else and I think it will be less expesive in the long run too.

as far as eating the brake seals that is false. DOT 5 synthtic will.

Mighty-Mouse

Castrol SRF is just a very, very good DOT 4 fluid. It's perfectly safe.

I've never heard anyone claim SRF was hard on seals or anything else.


If it wasn't for the price everyone I know would use it exclusively.

John Shiels

I have heard that before. I don't believe it at all. I do think if that was the case they would have huge warnings on the bottle. I have never inccured a problem. Some see the black in the fluid and think it is eating the seals. LG told me what caused that but I forgot at the moment. I have at least 4,000 track miles with it.

RogueVette

When was the last time a Mallet tuned car did anything special on a track....Listen to LG and DRM.

Lancer033

I was once told that any DOT 4 would eat seals and not to use it. I don' use SRF, but too many people use it both on this forum and at the tracks here for me to believe that it does any harm

John Shiels

I don't believe it but I think Mallet does have much knowledge.

RogueVette

I'm sure they do but there cars are perenial underperformers especially for the money (except that crazy dinosaur car) When it comes to high performance track results I would rather listen to those that actually get results and Mallet does not fill the bill.

Mighty-Mouse

DOT 5 silicone based fluid has been known to harm seals by decreasing the hardness (making them softer) and therefore accelerating wear.

Maybe people are mixing up Synthetic fluid and Silicone Fluid, since silicone fluids are synthetic? It's not the same thing because DOT 3,4,5.1 synthetics are not silicone based.

DOT 3, DOT 4, DOT 5.1 are all compatible with any brake system.


There are a few reasons why your brake fluid turns black:

Water in the brake system can cause internal corrosion (rusting) of the metal and deterioration of the rubber parts of the brake system from the master cylinder through the brake lines and seals down to the wheel cylinders and caliper pistons.

But the main reason is simply because the fluid is being burned from excessive heat.

I'm not sure, but the fluid being synthetic may exaggerate this color change. I've never worked with synthetics from an engineering standpoint.

Brake fluid should be changed at a minimum every 2 yrs. or 24,000 miles. Way sooner if you track or auto-x.

On a side note:

There is a lot of mis-information about DOT 5 silicone brake fluid. While it's true that it will not absorb water, it doesn't stop moisture from entering the brake system.

The water will form into pockets of pure water.

This water will make it's way to the calipers and plain water boils at a very low 212 F.

VERYSOON

I went through this same inquiry.
After hearing from lots of informed people here I went with castrol srf for prepping my car for the track. I believe everyone would use it if it were not so expensive.
I talked with one racer here about it. I said it costs more than a great bottle of scotch. He said brakes were more important than scotch. I agree.
The bottle does say something like 'due to the properties of this product the fluid should be changed every 18 months.' Don't know why but I plan to do it.

Nice to have the best product available in the C5.

g

Mikelly

I'm using GS610... Haven't had any issues...
Mike

0Randy@DRM

SRF is the best fuild out there at this time. We have been using it for many years without any problems. I was watching the 24 of Le mans, the factory prototype Audi came in with a brake duct issue. They fixed the duct in a stupid fast time. Topped it off with a can of Castrol SRF and went on to win the race. IT'S GOOD STUFF.

Thanks
Randy

C6RAPTOR

Randy
This 10 year old post is the only post I could find on the subject of Castrol SRF brake fluid seal problems.
I have been using SRF for 8-9 years for my brakes & clutch fluid.
I recently installed Tilton master & slave cylinders and found out from Tilton that SRF causes the seals to swell . Tilton stated that they tested all of the high temperature brake fluids and SRF caused swelling faster then the other fluids tested. Swelling started in three months.
I never had a problem with leaking with my OEM master or slave cylinders and Tilton stated that they use the same seal material as OEM.
I still have it in my Tilton clutch & Stoptech brake systems.

froggy47

Ask Tilton for a copy of their "white paper" on the test.

C6RAPTOR

The following is a recap of a telephone conversation I had with Tilton:

Gary,

Correct, I would expect similar swelling with the OEM and Tilton slave seals. You may never see a problem caused by the swollen seals, but if you do, it will probably be a while down the road. In our seal soak testing, we found that the seals softened and swelled about 3-4 months sitting in a jar of fluid. Is this swelling and softening enough to cause a problem in normal use of the slave? I can’t really say. We just put this statement in our 6000-Series HRB instruction sheet since most of these are used in hot rod applications where the vehicle may not be used much and the same fluid is used for many years.

Kirk

From: Gary Bowler [mailto:gary@grbowler.com]
Sent: Friday, July 15, 2016 10:29 AM
To: 'Kirk Skaufel (Tilton)'
Subject: RE: Castrol SRF In a Tilton Master

Kirk

As a recap of our phone conversation I understand that the Castrol SRF will make the seals in my Tilton system swell over a period of time. You also stated that the seals used in the Tilton 6000 series is the same a OEM slave cylinder seals that would also be affected by the SRF fluid over a period of time.
So in other words there is no change in seal swelling between the new Tilton slave or the OEM slave using SRF fluid but I may need to change seals in 2-3 years.

Respectfully

Gary

Part of an earlier email answer from Tilton:

It isn’t that you cannot use high temperature brake fluids with our hydraulic release bearings, we just recommend not using it to reduce the chances of seal swelling and provide the longest service life possible. We have tested our master cylinder seals and hydraulic release bearings seals with many different high temperature brake fluids. Some fluids swell the seals more quickly than others. Even if the seals swell, you many never see an issue or it may be a very long time before you do. On the other hand, of the fluids we have tested, SRF did swell seals the most quickly.

The following is email I sent Castrol after reading the instructions on my Tilton slave cylinder:


From: Gary Bowler [mailto:gary@grbowler.com]
Sent: 15 July 2016 03:31
To: Cat, Enquiries
Subject: Castrol SRF In a Tilton Master

I have been using Castrol SRF in my Corvette for my StopTech Racing brakes and OEM clutch master & slave fluid for many years and have found it works great under track conditions.
I recently installed new Tilton clutch master and slave cylinders in the care for use with a race twin disk clutch.
I just read the following in the Tilton Instructions for the slave cylinder and need to know if I need to be concerned. I have Castrol SFR in the system installed before I read the instructions.
Is there anything in the Castrol SRF fluid that would affect the seals? Most all the racers I know use Castrol SFR and this is a first for me.
HYDRAULIC RELEASE BEARING BLEEDING
1. Fill the master cylinder reservoir with DOT3 or DOT 4 brake fluid.Do not use DOT 5,
silicone based or high temperature resistant brake fluids designed for more than 550ºF
as some will cause the seals to swell.
[/COLOR][/COLOR][/COLOR][/COLOR][/COLOR][/COLOR]2. Apply light force on the clutch pedal. You want enough force to hold the bearing out
against the clutch diaphragm spring, but not enough to compress the clutch
diaphragm spring.
3. Open the bleedscrew that is attached to the bleed line on the hydraulic
release bearing.
4. Completely stroke the pedal and hold the pedal down.
5. Close the bleedscrew that is attached to the bleed line on the hydraulic release bearing.
6. Let the pedal return to its relaxed position and wait a few seconds.
Repeat Steps 2 through 6 until all air is removed from the system.
Note: Do not stroke the pedal again before the pedal stop is set.

http://tiltonracing.com/wp-content/u...ies-HRB-V2.pdf


http://tiltonracing.com/wp-content/u...ies-HRB-V2.pdf

froggy47

Thanks, that's good stuff & important. Personally I use Wilwood 570 with zero issues, however, I don't track where HUGE braking zones really "tax" the fluid.

I don't doubt you or Tilton. Just a quest for good information to make decisions.

C6RAPTOR

You had a good point about a white paper on the test. I have no idea how scientific the Tilton test was. The person I talked to stated that they place the seals in containers with all the different brands of brake fluids and take measurements.
I also have no idea if this swelling of the seals can cause a leak or any other fault in the operation of the subject equipment or not.
I am going to continue using SRF because it has worked for me for over 9 years .

TrackAire

I would think if you haven't had an issue in over 9 years, I wouldn't change either.

There are many types of materials seals are made out of....it is hard to say what Tilton is using compared to an OEM that probably uses something that might not be as exotic but is designed to last 20 plus years with a variety of brake fluids, environmental conditions and temperatures.

C6RAPTOR

I asked that question.
Tilton stated that they use the same seal material as OEM and the supply clutch hydraulic hardware to OEM

froggy47

Well that sounds sort of scientific. I guess. You really don't know how "controlled" it is, what seals the containers had, etc.

If it ain't broke, don't fix it.....