Oils, Fluids and Sealer› Oils, Fluids and Additives

Castrol

SRF Racing Brake Fluid

$74.99

SKU: Castrol-SRF

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
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Easy — 1–2 hours

Overview

It boasts a dry boiling point of 590°F and a wet boiling point of 518°F, exceeding DOT 4 specifications. This fluid is an excellent choice for vehicles using metallic brake pads and is compatible with ABS braking systems due to its resistance to foaming.
Show original supplier description
Its exceptionally high dry boiling point of 590°F and wet boiling point of 518°F significantly surpass standard DOT 4 specifications. This makes it ideal for situations where brake temperatures soar, such as during intense track use with high thermal conductivity metallic brake pads. Engineered with advanced silicon ester technology, Castrol SRF is less hygroscopic than conventional brake fluids, meaning it absorbs less moisture over time. This characteristic helps maintain its high-temperature performance and prevents the deterioration often seen in standard glycol ether fluids. Furthermore, its resistance to foaming ensures consistent pedal feel and reliable operation, even in vehicles equipped with ABS braking systems. Castrol SRF Racing Brake Fluid is compatible with other DOT 3 and DOT 4 fluids, though it is not compatible with silicone-based (DOT 5) fluids. It is packaged in convenient 1-liter (33.8 fl oz) plastic bottles for easy pouring. Users have reported exceptional performance and confidence in demanding situations, with many considering it the benchmark for racing brake fluid.
Vehicle Symptoms
  • brake pedal goes soft after repeated hard stops
  • brake fade during long track sessions
  • spongy brake pedal feel after aggressive driving
  • brake fluid boiling smell from calipers
  • increased stopping distance after hard braking
Relevant Conversations
  • Why does my brake pedal go soft after 3 hard laps? Need better fluid?
  • Castrol SRF vs Motul RBF 600 track comparison
  • Brake fade with stock fluid on track day – should I upgrade?
  • How often do you flush Castrol SRF for autocross?
  • Can I use Castrol SRF in a daily driver with DOT 4?
  • Best high boiling point brake fluid for heavy braking zones
  • Symptoms of boiling brake fluid – mushy pedal and smell?
  • Castrol SRF wet boiling point real world review
  • Is Castrol SRF worth it for HPDE beginners?
  • Will SRF fix my low brake pedal after track weekend?

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandCastrol
Part NumberCastrol-SRF
CategoryOils, Fluids and Sealer

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Shipping

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