Choosing the right hydraulic oil is key to keeping your machines running smoothly. It not only transfers power but also protects parts, reduces wear, and keeps the system clean. The wrong oil can cause damage, higher costs, and poor performance.
At Fubex Lubricants, we offer high-quality hydraulic oils for all types of engines. Enjoy fast shipping, a price match guarantee, and no-questions-asked returns. Need help choosing the right oil? Call us at +971 50 544 9614 — our friendly team is ready to assist!
This checklist will guide you through everything you need to know—viscosity, additives, filters, and more. Pick the best oil, save money, and extend your equipment’s life. Keep reading to learn how.
Hydraulic Oil Features and Functions
- Viscosity – This means how thick or thin the oil is and how well it flows at different temperatures.
- Low-temperature flow – The oil should move easily even when it’s very cold.
- Thermal and oxidation stability – Stops dirt and sludge from building up inside the system.
- Water resistance – Keeps the oil from mixing with water and causing damage.
- Clean and filterable – With regular maintenance, the oil stays clean and free of harmful particles.
- Demulsibility – The oil can separate water from itself, keeping the system safe.
- Anti-wear protection – Helps protect parts and makes them last longer.
- Corrosion control – Stops rust and damage to metal parts.
- Eco-friendly – Some hydraulic oils are biodegradable, which is better for the environment.
What Does Hydraulic Oil Contain?
Hydraulic oil is made of different ingredients that help it work well. Most hydraulic oils include mineral oil and esters. Esters are special carbon-based compounds made by mixing acids with other chemicals.
Other important parts in hydraulic oil can be glycol, silicone, and ethers. Ethers are liquids that can catch fire easily and have oxygen that connects two chemical groups.
To make hydraulic oil even better, companies add special additives. These additives help stop rust, corrosion, and water contamination. They also make the oil and the hydraulic system last longer.
It’s very important to always use the right hydraulic oil for your machine. Using the wrong oil can cause poor performance, and in serious cases, it can even damage the system permanently.
When Oil Should Be Avoided
Most hydraulic systems use oil-based fluids, but there are times when oil is not safe to use. For example, if the system is near sparks, open flames, or very hot metal, oil can be dangerous. A leak in a high-pressure system could cause a fire or even an explosion in these risky areas.
This is why special safety rules exist for such environments. The term “ATEX” comes from French words meaning “explosive atmospheres.” It refers to the safety standards used to control and prevent explosions in hazardous places.
Which Type of Oil Should Be Used?
There are many kinds of hydraulic oil, and choosing the right one is very important. The oil you use depends on the system, the conditions, and the type of equipment. Hydraulic oil is mainly used in mobile, industrial, and aviation equipment, but each needs a different type.
Hydraulic oil for cold weather
In very cold environments, special oils are used that stay smooth and don’t freeze. Antifreeze additives are often mixed in to help the oil flow in low temperatures.
Heat-resistant hydraulic oil
When oil gets too hot, it becomes thinner and flows too easily. This can cause leaks or make the oil lose its strength. For hot conditions, additives are added to keep the oil thick enough to protect the system.
Oil for high pressure
In systems that run under very high pressure, the oil must still work well. Heavy-duty oils are used here, often with additives that stop wear and damage. These are common in tough jobs like construction equipment.
Eco-friendly hydraulic oil
In places where leaks or spills could harm nature, biodegradable oils are recommended. These are often made from rapeseed or other vegetable oils, which break down safely in the environment.
Hydraulic Oil Viscosity
Viscosity means how thick or thin oil is and how smoothly it flows. If the oil has high viscosity, it is thicker and harder to move through the system. If the oil has low viscosity, it is thinner and flows more easily.
Viscosity is measured in Centistokes (cSt), usually at 40°C and 100°C.
Viscosity and temperature
The thickness of hydraulic oil changes with temperature. When the oil gets hot, it becomes thinner and flows faster. When it gets cold, the oil becomes thicker and moves slower. It works the same way as cooking oil—it flows faster when heated.
Hydraulic oil needs the right viscosity so the system runs smoothly in all conditions, even when temperatures change. This is very important for machines that work in tough environments.
Viscosity index
The viscosity index shows how much the oil’s thickness changes with temperature. A low index means the oil changes a lot when the temperature goes up or down. A high index means the oil stays more stable, which is better for machines working in different conditions.
Using the wrong viscosity oil can cause damage, poor performance, and shorter life for your hydraulic equipment, even if the oil has other good features like anti-wear or anti-rust protection.
Hydraulic Oil Life
Taking care of your hydraulic oil is very important for keeping systems and parts in good condition. Modern hydraulic systems are smaller than before, so they use less oil. But because pumps now work harder and create more pressure, the oil gets hotter. Hotter oil means more oxidation and stress on the oil, which can shorten its life.
How long hydraulic oil lasts depends on the quality of the oil, the working conditions, and how clean it stays. In the right conditions, good quality oil can last at least six months. With proper care and maintenance, it can last even longer.
Oil Temperature
Temperature plays a big role in oil life. In most industrial systems, oil runs at around 60°C, but it can rise to 85°C. While this is normal, keeping oil at high heat for too long will shorten its life. For every 10°C rise in temperature, oxidation speeds up, which reduces oil life.
Oxidation
Oxidation happens when oil reacts with oxygen, creating acids. These acids form sticky by-products, like varnish, that can clog filters and strainers. High temperatures speed up oxidation, so if it gets too bad, the only solution is to change the oil.
Contamination
Things like water, air, dirt, fuel, or mixing with other oils can contaminate hydraulic oil. Contamination weakens the oil and shortens its life, so keeping the system clean is very important.
How to Make Your Oil More Cost-Effective
To get the most out of your hydraulic oil, you should:
- Use high-quality oil – Always choose oil from a trusted supplier who can also give technical support.
- Watch operating conditions – Keep the oil clean and free from dirt or other particles.
- Change oil when needed – If oil becomes too dirty or oxidized, replace it before it causes damage.
While good care helps, hydraulic oils are also designed with special additives that make them last longer and perform better in different conditions. The type of additives depends on how the oil is used.
- Anti-wear additives – Protect machine parts and make them last longer.
- Cold flow additives – Keep the oil working smoothly in very cold environments.
- Anti-foaming agents – Stop bubbles and foam from forming, which can reduce lubrication and cause damage.
- Antioxidants – Slow down oxidation, reduce sludge buildup, and extend oil life.
- Anti-rust additives – Create a protective layer that prevents rust and corrosion.
By combining proper maintenance with the right additives, you can make your hydraulic oil more cost-effective and extend the life of your equipment.
Also Read: How to check hydraulic oil quality
Hydraulic Filters and Oil Life
A hydraulic filter is one of the most important parts of a hydraulic system. It protects the oil by removing dirt and tiny particles before they can cause damage. Without the right filter, contaminants can block the system or wear down components. This shortens both oil life and machine life.
Choosing the right hydraulic filter is very important. The right filter keeps the fluid clean, prevents breakdowns, and helps the system run smoothly.
At Fubex Lubricants, we work with many trusted suppliers of hydraulic filtration equipment from around the world. This includes both leading brands and specialized products, such as ATEX-approved filters designed for use in explosive or hazardous environments.
The Importance of Choosing the Right Heavy-Duty Hydraulic Oil
Hydraulic systems are the power source for machines like excavators and cranes. The hydraulic oil not only transfers power but also protects the system. Choosing the right oil is very important because it affects machine efficiency, part life, maintenance costs, and overall reliability. Using the wrong oil can lead to higher expenses, more breakdowns, and shorter equipment life.
Viscosity Grade (ISO VG 32–68)
Viscosity means how thick or thin the oil is. If the oil is too thin, it won’t protect the parts. If it’s too thick, it wastes energy and slows the system. The right viscosity keeps the oil flowing smoothly, increases efficiency, and reduces wear on components.
Additives for Protection
Good hydraulic oils include additives like anti-wear, anti-foam, anti-oxidant, and seal protectors. These additives keep parts safe, extend oil life, and lower maintenance needs. Premium oils with strong additive packages can last longer and save a lot of money over time.
Temperature Performance
Machines often work in extreme heat or cold. Hydraulic oil must handle temperatures from -10°C to 80°C without breaking down. Oils with good thermal stability stay reliable in all conditions and protect against overheating.
Contamination Control
Clean oil is key to long equipment life. High-quality hydraulic oils resist dirt, water, and other contaminants, while also working well with filters. Keeping oil clean reduces part damage, lowers repair costs, and makes machines last longer.
Also Read: What is AW Hydraulic Oil?
Final Takeaways
Choosing the right hydraulic oil isn’t just about keeping your system running—it’s about protecting your equipment, saving money, and boosting performance. By focusing on viscosity, additives, temperature range, and contamination control, you ensure your machines deliver reliable results and longer service life.
FAQs
Q1: How do I choose the right hydraulic oil?
Check your machine manual for the correct viscosity and additives, and match the oil to your operating temperature and working conditions.
Q2: What is the difference between ISO 32 and AW 32 hydraulic oil?
ISO 32 only refers to the oil’s viscosity grade, while AW 32 is a hydraulic oil with the same viscosity but also contains anti-wear additives for extra protection.
Editor-at-Large
A passionate writer in the lubricant industry, Awais Iqbal has been covering oils, greases, and industrial fluids since the start of his career. At 25, he’s already written for blogs, catalogs, and brand guides across the UAE. Awais’s insights help companies connect with their audience, and his clear, helpful writing style is trusted by brands in the region.
