I was doing some research on various brake fluids when I came across this page about Castrol SRF.

http://www.racerpartswholesale.com/srf1.htm

It says --
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.
...
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.
---


That probably also explains the exceptional price. Anyways, can anyone give some insight into this? Is silicon ester DOT5 brake fluid?

Thanks,
Tim

 

Pretty sure it's DOT 4.

I don't think it's a good choice on street/track vehicles that are not flushed very frequently. While it has excellent wet/dry temperature characteristics, it is more hygroscopic (absorbs more water) than some other choices, like Ate Super Blue or Motul 600.

See the Note thread on Brake Fluid

 

So not put silicon-based or Dot5 brake fluid in the S2000's brake system. It isn't compatible with the seals! right?

 

[QUOTE]Originally posted by pellisS2k
[B]So not put silicon-based or Dot5 brake fluid in the S2000's brake system.

 

SRF is *not* DOT5... because the DOT 5 spec is only for silicone fluids... which SRF is not.