Product Data - Castrol SRF  |  Product Data - Performance Friction Z Rated  |  DOT Specifications

There are 2 types of brake fluids commonly available today:

Glycol-ester blends ("glycol-based")

More common are the glycol-based.  These glycol-based fluids normally have low compressibility but are "hygroscopic" in nature.  This means they are able to absorb water from the atmosphere.  This contamination process occurs whenever brake fluids are exposed to the atmosphere, and even occurs somewhat through the plastic bottles most brake fluids are packaged in.  This is the reason that all brake fluids must be used fresh.  The susceptibility of brake fluids to hygroscopic contamination can be judged by comparing the "dry boiling point" and "wet boiling point" of the fluid:  the greater the difference is between these two ratings, the more hygroscopic is the nature of that fluid.  This concept is important, as it is the absorbed water that gasses off (boils) first inside the brake system and adds to the "spongy/soft/long pedal" effect.  Pay no attention to the large numbers used by the marketers to describe the product, as they can be very misleading.  The dry boiling point of glycol-based brake fluids seldom exceeds 304°C (580°F), even though you'll see 600, 610 and 660 as a label description.  The use of PFC caliper temperature stickers (Part # 032.0007) is highly recommended to monitor brake fluid and caliper seal condition.  If the calipers exceed 210°C (430°F) for an extended period, the brake fluid and or caliper seals will deteriorate.

High percentage ester content blends ("ester-based")

High percentage ester blends have the promise of higher dry and wet boiling points.  The ester base used in manufacturing these fluids is not hygroscopic at all.  However, they are blended with a percentage of glycol for several reasons including cost (ester is more expensive to manufacture than glycol), pedal feel (ester is by nature more compressible than glycol), lubricity and seal conditioning.  The most common ester-based brake fluid on the market, and the established standard in the racing industry, is Castrol SRF.  It has a proprietary formulation and effectively combines the best properties of the ester base (stability at elevated temperatures and low hygroscopic characteristics) with compressibility near that of glycol-based fluids.  PFC recommends Castrol SRF racing brake fluid because of decades of proven consistency and performance.  However, not all high ester blends are equal.  In many cases although they may have less water content to boil, ccompressibility is not as good at elevated temperatures, and the soft/spongy/long pedal effect is the same.  Regardless of which brake fluid is used, frequent and correct bleeding should be considered part of proper race preparation.

Product Data - Castrol SRF      

Castrol SRF Racing Brake Fluid is a high performance brake fluid of special value in competitive motorsport where extreme braking conditions are encountered.  It has been especially formulated to maximise braking performance under arduous competitive conditions.  In order to achieve the optimum benefits in such applications, patented silicon ester materials have been emplyed in a unique Castrol formulation.  As a result of its unique properties and to maintain excellent vapour lock and corrosion protection, we strongly recommend that Castrol SRF be drained and refilled every eighteen months.

Application:  Castrol SRF is suitable for all disc and drum brake systems used in motorsport with the exception of those for which a mineral oil is prescribed.  It complies with the requirements of the following specifications:

• US FMVSS 116 DOT 3 and DOT 4
• SAE J1703
• ISO 4925
• Australian Standard 1960 Grade 3

Features & Benefits:

• Race Proven:  Widely used in racing, from Formula One World sports cars to Group A and 500cc Grand Prix motorcycles;
• High Boiling Point:  The exceptionally high dry boiling point (higher than 300°C) makes Castrol SRF ideal for use under arduous braking conditions such as rallying or racing.  Castrol SRF exceeds the boiling point requirements of DOT 5 brake fluids;
• High Vapour Lock Point:  Castrol SRF has a very high vapour lock point (the more important measure of high temperatures performance under actual braking conditions)  and has the additional advantage of sustaining high vapour lock point characteristics during its service life;
• Compressibility:  The compressibility of Castrol SRF is very similar to that of current DOT 3 and DOT 4 fluids.  It can therefore be filled into any braking system used in motorsport with the exception of those for which a mineral oil is prescribed;
• Miscibility:  Castrol SRF is miscible with all conventional fluids meeting the US Federal Standards FMVSS 116 DOT 3 and DOT 4, ISO 4925 and current SAE J1703.  The miscibility of Castrol SRF with conventional brake fluids means changing the brake system to Castrol SRF is easy.  Drain and flush out the conventional brake fluid with Castrol SRF then top up the system with Castrol SRF.  Although Castrol SRF is miscible with conventional brake fluids, topping up Castrol SRF with conventional brake fluids will reduce the benefits of the product;
• Compatibility:  Castrol SRF is compatible with seal rubber and metal materials used in braking systems using conventional polyglycol brake fluids;
• Bleeding:  Castrol SRF is easy to bleed like conventional brake fluids.

Characteristics:

Product Data - Performance Friction Z Rated      

Performance Friction Z Rated high performance glycol based brake fluid is an everyday performance brake fluid and an excellent replacement to OEM fluids.  It has extremely low compressibility and excellent lubrication properties.  Z-Rated fluid is non-corrosive to brake system components and has been proven to be easier on both natural and synthetic rubber seals.

Application:   For racing, high performance and medium duty applications - all applications that require DOT3 fluid.

Features & Benefits:

• Z Rated DOT3 non-compressible severe duty brake fluid;
• Offers improved pedal feel and ABS function.  It eliminates mushy pedal feel and long pedal caused by low quality brake fluids;
• Non-silicon.

Characteristics:

DOT Specifications