Most hydraulic clutch systems use which hydraulic fluid?

The use of DOT 3 brake fluid in most hydraulic clutch systems is due to its properties that make it suitable for the conditions and requirements within these systems. DOT 3 brake fluid is a glycol-based fluid that has a high boiling point, which helps prevent vapor lock under extreme conditions, such as during heavy or prolonged drag on the clutch.

Moreover, this fluid is designed to be non-compressive, providing a consistent feel and response when the clutch pedal is engaged and released. Its compatibility with rubber seals and components commonly found in hydraulic clutch systems also ensures durability and prevents leaks or malfunctions that could arise from using a fluid that isn't appropriate for high-pressure applications.

In contrast, motor oil is not designed for hydraulic applications, and using it could lead to poor performance and potential failure of the system. Transmission fluid, while useful in the transmission itself, does not meet the specific requirements of hydraulic clutch systems. Hydraulic oil, on the other hand, is more suitable for machinery and actuators but lacks the necessary properties required for optimal operation in clutch systems, such as the necessary boiling point and the ability to handle moisture.