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What Is Hydraulic Fluid? Hydraulic fluid, often called hydraulic oil, is a crucial component in hydraulic systems. It is a specialized liquid that transmits power within machinery, enabling controlled movement. This fluid is viscosity, additives, and stability under pressure are vital for optimal system performance. It lubricates components, minimizes wear, and resists heat and corrosion, ensuring smooth operations in industries like construction, manufacturing, and aviation.

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