Mr. C4

Which type of brake fluid is to be used in our cars, silicone or non silicone based products?

I'm thinking Motul RBF 600 or Motul 5.1

Ciao,

Johannes

Bass GT3

Johannes,

Use Castrol SRF. Does exactly what it says on the tin. I think it is NON Silicon that is used from factory, so be 100% sure, DO NOT use the wrong type.

Regards,

Steve

CME

Has anybody used the ATE Super Blue or Type 200 fluid. Been using that on my E30 M3 and was wondering if that would be ok for the GT3. Is the Castrol just better than the ATE?

Thanks.

Chet

FixedWing

DOT4.

Brake fluid has been discussed here soooo often. The last time was about a week or so ago.

Stephen

Mr. C4

Stephen,

Excuse me for asking but I could not find any thread wheter to go silicone or not has been discussed/answered.

NJ-GT

Castrol SRF here

DCLee

Don't use ATE Blue, it's like cheap Kool-Aid. Use Castrol SRF or Motul 600. Do not use any silicone fluid, period.

Lee in D.C.

plima

To help clarify, Porsche requires DOT-4 (eg Castrol SRF, Motul 600, ATE Super Blue, etc.); Silicone fluids are all DOT-5. Don't use silicone/DOT-5. As for the DOT-4 fluids, there are a ton of posts here on that subject.

FixedWing

Ok ... needs to be DOT4. I use Castrol SRF. Castrol SRF is DOT4. This is unquestionably the best with a higher wet boiling point. I use it because I do not change my fluid very frequently. Others who do change very frequently use one of the racing DOT4 fluids. For them, these are cheaper than Castrol SRF and becuse they are changing it frequently they need not worry about the wet boiling point. If you do not track the car then you are better off with a non-racing DOT4 fluid as it will need to be changed less often than a racing fluid.

Silicone is DOT5. This is usually used for show cars. Sometimes it is possible to convert a car to DOT5. Sometimes it isn't. I imagine some of our brothers with older Porsche have tried this. I have converted an old Fiat to DOT5 successfully and previously run other cars on it. But I know of no 996 GT3's that have been converted. The advantage is that silicone will not damage the paint if it spills (hence show cars with less leak-proof brake systems) and is more stable so can be left in longer. The disadvantage is that it is more compressable and might have a lower dry boiling point. There might also be a problem with the ABS. So you could try to use DOT5 if you wanted but you would be the guinny pig and I really don't think it is such a good idea.

Stephen

NJ-GT

I don't get it.

People don't use Castrol SRF because is too expensive. $65.

They do expend a lot more on tires, gas, track fees, car wash, brake pads, alingment, etc.

Greg Fishman

Iknow guys that use ATE in their 996 Cup Cars and I can't imagine a street driven GT3 needing anything more than ATE or similar fluid. But if you track the car a lot the SRF might be good insurance.

I have used ATE on my race car and not had a problem with it boiling, but I do have good air ducting.

FixedWing

I do get it NJ. Castrol SRF has almost the same dry boiling point as other racing fluids. If you are going to change your fluid every month or two (as in, after every event), then there is absolutely no advantage to SRF. So why pay more for no benefit?

If you are going to leave the fluid in 6+ months then it is a completely different story. The racing fluids take up water very quickly -- more quickly than non-racing fluids. That's when SRF has a clear advantage and become worth the extra money.

And that's why I use SRF.

Stephen

One of the many tables listing brake fluid boiling points

redcar1

OK, so is there only one Castrol SRF? Technically, is it NOT racing fluid?
Porsche does NOT use it "from the factory", do they??
Does it need to be changed less frequently than other fluids?
If so, then it would seem to be the only logical choice for a high performance application, except one with very frequent full system bleedings, is that right?
Thanks,
Mark McKenzie

FixedWing

What is "high performance" ??? The only real difference between all of the DOT4 fluids is their wet and dry boiling points. The honest truth is that few people will ever get their fluid close to hot enough to boil. At the least, it takes a lot of track use. So most people should be satisfied with normal DOT4 and will gain nothing from higher temp fluid (and in fact, could end up with more corrosive water in their system if they left it in long enough).

Having said that, if it ever does boil it is going to be a very big deal and will certainly get your attention.

Castrol SRF is considered a racing fluid but it is special. Castrol has come up with a way to prevent the water in the fluid from lowering the boiling point by as much as the other fluids. No one else can do this. And that's why they get to charge so much.

From the table I referenced above, Motul Racing 600 and SRF are almost identical on their dry boiling points (585/590 F). But their wet boiling points are quite different (421/518 F). And that is the beginning and the end of what SRF is about. Simply the difference in the wet boiling point.

Porsche does not use SRF for their street cars. Probably because of the cost. But SRF is DOT4 and Porsche specifies DOT4 in their cars so it does comply with their specifications. However, if you start telling service that you are using SRF then don't be surprised if they start thinking you are tracking your car.

Stephen

Recent Rennlist discussion of brake fluids

Castrol SRF technical info

tdf360

I don't agree, I use it and know any number of other track-oriented drivers who are completely satisfied also. You can spend more, but if you just do 8 or 10 events a year like many of us Ate is perfectly satisfactory, in my opinion.

Gary