The Many Uses of Hydraulic Oil

Whether your hydraulic system is in a car, a lift, a plane, or cruise ship, there is a magical elixir of mineral oils, glycols, esters, and additives to fit the situation. Hydraulic oils are used for many mechanical purposes that include high pressure, extreme temperature, and heavy-duty applications.


Braking systems rely on hydraulic fluid to smoothly bring your car to a stop. Brake fluid, a specialized type of hydraulic fluid, has a high boiling point, which makes it more appropriate for the heat-producing function of braking a car, motorcycle, truck, and even some bikes. These hydraulic fluids are mostly made of glycol ethers or refined mineral oils.

Heavy Machinery

Bulldozers, excavators, cranes, tractors, and lifts, use hydraulic systems to create enough force to move materials and equipment. Many of these systems employ hydraulic cylinders that transfer power through the hydraulic oil between cylinders, often with the assistance of motors. When high-pressure, heavy load conditions are present, a fluid with a higher viscosity grade and anti-wear additives work the best. For plows and applications that operate in extremely cold temperatures, anti-freeze additives are also considered.


Hydraulic oils used in aviation or aerospace applications must fulfill a host of different demands, because they come into contact with a wider range of environments. A high viscosity index, low-temperature properties for high altitudes, and oxidation resistant additives make the oil more reliable for such a demanding industry. Aviation-specific oils are used for flight controls, landing gear, brakes, wing movement, and other aircraft hydraulic motors and pumps.


Boats and ships require hydraulic oils for maneuvering, and these hydraulic applications include steering systems, bow and stern thrusters, anchor windlasses, and shell doors, among others. Hydraulic oils in the marine industry are often biodegradable due to regulations and the fragile environment in which they operate. It is also necessary that these fluids are long-lasting and efficient in cold temperatures.


Non-mineral oil hydraulic fluids, especially water-glycol or phosphate ester synthetics, are suitable for moderate operations where it is dangerous to generate too much heat. Military and metal industry applications, die casting machines, and furnace hydraulic systems commonly use these oils to prevent fires.

Environmentally Friendly

In addition to the maritime industry, biodegradable oils are used in off-shore drilling, forestry, and other applications where leakage can damage the environment. These hydraulic fluids are made from vegetable oil, synthetic esters, and poly glycols. Vegetable and animal oils are nontoxic, but can be less effective and easily oxidize compared to the other water non-soluble hydraulic oils.

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