Castrol React SRF Racing DOT4 Brake Fluid

Brake fluid is one of the most important, yet overlooked, components of your vehicle and critical to high performance driving. See our guide to choosing the right Track Day and Racing brake fluid for you.

Today, Castrol is a household name, but its history dates back to the late-1800s. Their researchers found that adding castor vegetable oil to other lubricants made for great cold start-up characteristics with high operating temperatures. In fact, Castrol was trusted in the first trans-Atlantic flight. Today they are still known as a leader in lubricant technology.

Production battery EVs tout regenerative braking and "one pedal driving" as a prominent feature. Regenerative braking utilizes the vehicle's electric motor to slow the car down. While this is great for energy reuse and saving brake consumables, the factory fill brake fluid is nowhere near up to the task of track driving. Given the massive amount of friction necessary to slow down the weight of a modern EV, it is easy to overheat the OEM fluid leading to loss of pedal feel or, worse yet, serious brake failure.

Nicknamed "Liquid Gold", Castrol React SRF Racing Brake fluid is widely regarded as the best brake fluid avaiable. With a Wet Boiling Point of 270°C/518°F and Dry Boiling Point of 328°C/590°F it offers high performance stop after stop for the life of the fluid. If you are a heavy, late braker on track or simply want the best of the best, this is the fluid for you. Sold in 1L plastic bottles, so you are set for a full flush.