How Often to Change Hydraulic Fluid in a Log Splitter?

Just like any machine, a well-maintained log splitter will surely give you years upon years of good use. Aside from your splitter’s engine oil, you must also check your splitter’s hydraulic system, most especially the hydraulic oil, hydraulic pump, and hydraulic fluid.

Neglecting these log splitter components can lead to hydraulic system failure and overall tool failure as well.

Hydraulic log splitters require well-maintained hydraulic systems to perform well. You must make sure that your splitter’s maintenance schedule is closely followed all year round, not just during the winter months. 

Related: Best AW 32 Hydraulic Oil

How often should you change hydraulic fluid in a log splitter?

To keep an electric or a gas-type log splitter in tip-top shape, you must check its hydraulics system regularly. You should change your fluids after around 100 hours of use. Also, before you use a splitter, check if the reservoir tank for the hydraulic fluids is full.

How to check the hydraulic fluid in a log splitter?

To check if the hydraulic oil tank is full, place a stick in to determine the fluid level. You can also sight the tank if it’s full or not. When filling the tank with hydraulic fluid, you must fill the tank but don’t let the fluid overflow.

To check if the fluid is leaking, use a dry piece of cloth, paper, cardboard, or tissue. Wipe the underside of the tank to check for leaks.

What are the kinds of hydraulic oil/fluid used?

Hydraulic oil for a log splitter acts as a lubricant to improve the performance of the system. These are made from different kinds of ingredients including mineral oil, glycol, ester, ethers, and silicone. Log splitter hydraulic fluids are classified into the following types:


Hydraulic oil can burn when exposed to high-temperature conditions. If the fluid burns, it will leak and affect the overall capabilities of the system. This can also damage the entire hydraulic system. Thus, to reduce fire risks due to burning, log splitter owners use a flame-retardant hydraulic fluid.


Wear-resistant hydraulic oil or fluids is the recommended hydraulic fluid for high temperature and pressure environments. This type of fuel protects the hydraulic pump and other hydraulics system components from early wear and tear using a screen or a grill.


This kind of hydraulic oil is environmentally friendly and best for use in forests, farms, and preserves. This fluid has a biodegradable base so it will naturally degrade in water or soil in case of a spill.

Some additives used in a hydraulic log splitter

Most hydraulic wood splitter users include the following to enhance the system’s performance:

  • Anti-wear additives with anti-wear properties to extend engine life.
  • Anti-rust that protects the hydraulic components with a special coat against oxygen contact.
  • Anti-foaming reduces foam due to detergents.
  • Anti-oxidant to improve the life of the system and avoid regular oil changes.

The viscosity grade for these oils vary. To find out the right oil recommended for your splitter’s hydraulics, check the machine’s user manual. Check other fluids

How to change the hydraulic fluid in a log splitter?

All log splitter owners and users must learn how to maintain their equipment. Part of this is knowing changing hydraulic fluid. Remember these steps.

1.  Place a fluid tray or suitable container under the hydraulic tank.

The container must be big enough to accommodate 3 gallons of hydraulic oils from the reservoir tank.

2.  Remove the suction hose from the tank.

Check your owner’s manual for the location of the tank and how to remove the hose. Your manual will have your engine’s specific model’s needs, specs, and parts. Remove the drain plug.

3.  Loosen the inlet filter.

Clean the oil filter using a small rag and penetrating oil. If it has been too long we recommend changing the oil filter after typically after 100 hours of usage.

4.  Let the fluid drain to the container.

When the fluid tank is empty, reinstall the hose, cylinder, pump, and filter. You may now tighten the clamps of the hose. Most reservoirs won’t completely drain so slightly move the tank.

5.  Determine the hydraulic fluid levels with a stick or dipstick.

Fill the tank with fluid but don’t overfill when you do the oil change. How much hydraulic fluid will you use? How do you know the tank has the proper amount? Check the range marker on your dipstick. The tank must be filled with fresh fluid from this level.

6.  Prime the hydraulic log splitter pump

But first, disconnect the spark plug. Place the recoil starter; hold and rip it 10 times. Afterward, reconnect your spark plug and restart your engine.

7.  Engage the splitter wedge

Place the wedge to the farthest position from the beam and afterward, retract it to place it on its starting position. 

8.  Self-bleed the system

Move the control handle or pull cord to the front and back of the tank. Do this 10 to 12 times to remove any trapped air from the hydraulic system.

More tips to consider

Older machines also need regular oil replacements. Aside from this, take time to perform basic maintenance. Lubricate different components, check the different valve components, and replace any worn-out parts. Check leaks in the reservoir and fix these as necessary.

Replace torn hoses or any heat-damaged components. Your engine will lose power if these are not replaced right away. Always follow the manufacturer’s recommendations from your owner’s manual.

Get acquainted with the different log splitters motor and hydraulic systems including the reservoir tank.


Whether you have a gas-powered or electric log splitter, you must properly maintain your machine regularly to ensure maximum performance. One of the ways to maintain your log splitter is by changing the motor oil and hydraulic fluid.

You must change the fluid and filter at least every 100 hours of use and remember to use the appropriate type of hydraulic fluid for the best results.