What Hydraulic Fluid to Use In a Log Splitter?

The nights are starting to get cold, and this means that winter is just a few weeks away. In anticipation of cozy nights around a crackling fire, you probably have stocked enough good quality firewood already. For a more convenient firewood cutting, you might want to ditch your traditional axe and shift to a log splitter.

Why Use a Log Splitter?

A log splitter is a more convenient tool in splitting firewood. Instead of using manual labor- possibly breaking your back and hurting your hands, a log splitter gets the job done for you.

It splits firewood into specific dimensions with ease. The most common types of log splitter are electrical, manual, and gas.


This is the most popular type of log splitter in the market. The popularity can be associated with the fact that it caters to all situations, and operates on the same gas models. It is also lightweight, making transport and storage convenient.

You can set up this splitter at ground level or on a bench. Unlike other types, this one can be used practically anywhere as long as there is a standard electrical outlet. It also requires less maintenance, so you don’t need to stress maintaining a gas engine or changing fluids regularly.


A manual log splitter is easy to store because of its lightweight design. Depending on which allows the most convenience, you can choose between a hand-powered model and a foot-powered model. While some manual log splitters function using hydraulics, others require workforce and heights.

You may find a manual log splitter to require more effort, yet, it is still more convenient than using an axe.


For splitting larger logs, the best bet is a gas log splitter. It is designed for heavy-duty tasks and capable of handling up to 38 tons of logs.

The only downside is that this gas splitter may require regular maintenance, including regular fuel additions, oil changes, and spark plug replacements.

A gas log splitter is designed to suit all kinds of situations and all kinds of users. This one is built with versatility in mind. Thus, it is an ideal option if you plan on burning wood regardless of the season.

Thinking of an upgrade? We have updated our log splitter reviews for this year. You just might find you next one!

What is a Hydraulic Oil?

Hydraulic oil is both lube and a power transfer device. It lubricates the hydraulic system and serves as a means for the transfer throughout the system. What’s more, it is made from various ingredients, including ester, glycol, ethers, silicone, and mineral oil.

The primary hydraulic oil is classified into different types:

Flame Retardant Hydraulic Oil – Lubricant oil can burn under high heat conditions. When this happens, it can leak and lose the necessary properties. To reduce the risk of fire caused by the ‘burning’, a flame retardant hydraulic oil is used.

Wear-Resistant Hydraulic Oil – This is used for high-pressure and high-temperature environments where the system needs to cope with specific stressors.

Environmentally-Friendly Hydraulic Oil – This hydraulic oil is used in hydraulic machinery on environmentally sensitive sites such as farms and forests. A biodegradable base fluid makes up the oil, allowing it to degrade naturally in case of a spill.

Depending on how you prefer to use hydraulic oil, extra additives can help achieve machinery’s maximum performance under different conditions:

  • anti-foaming (reduces foaming within the fluid caused by detergents)
  • anti-rust (forms a protective coating to reduce damage from oxygen contact)
  • anti-wear (extends the life of the machinery, found explicitly in AW-type hydraulic fluids)
  • anti-oxidant (allows extended use without changing the oil)

Using Hydraulic Oil in Log Splitter

The right hydraulic oil for a log splitter is indicated in the engine owner’s manual. Some brands include hydraulic oil in the package, while others require you to make a separate purchase.

You can purchase hydraulic oils online at Amazon or from hardware stores, farm equipment retailers, and automotive supplies. It is recommended that you never operate a log splitter without the required hydraulic oil.

The most common approved hydraulic oil for log splitters is an AW (Anti Wear) 32 hydraulic log splitter oil. This type of oil lubricates gears, cylinder assembly and other mechanical parts during extreme heat and cold. Additionally, it pressurizes the hydraulic system.

When you activate the log splitter, the hydraulic system builds pressure with the oil. Once pressurized, the system initiates your motion for cutting the log.

You will need to replace the hydraulic oil and how much you need to replace would depend on the engine oil capacity of your log splitter. The oil produces sediment over time which can potentially damage the internal parts. To prevent this from happening, strictly follow replacement schedules.

As with any other equipment, nothing beats safety. Ensure that you read the instructional manual thoroughly and do not disregard safety instructions. Most importantly, use the machine for cutting wood only as it is not suitable for any other purpose.

Hydraulic Oil FAQs

What oil do I need for my log splitter?

AW32 hydraulic oil is recommended for use with a log splitter. It provides excellent antiwear protection, oxidation and corrosion resistance.

Why is my log splitter moving slowly?

Your log wood splitter may run low on hydraulic oil, or the pump may be experiencing a mechanical issue. Please refer to the owner’s manual for specific troubleshooting instructions.

Can I mix different types of hydraulic fluid in my log splitter?

Operating a log splitter without sufficient hydraulic oil can damage the hydraulic pump. Therefore, it is recommended only to use one type of approved hydraulic oil and not mix different types of hydraulic fluids.

Why is my log splitter not starting?

There could be two possible reasons: the tank might be very low on hydraulic oil, or the engine might be flooded. Again, please refer to the owner’s manual for specific troubleshooting instructions.