After every 150 hours of use, the hydraulic oil needs to be replaced with AW32 anti-wear hydraulic oil. To replace the hydraulic oil, follow the instructions below:

1. Make sure all moving parts have come to a complete stop before removing the batteries from the log splitter.
2. Place a container under the drain hole. Then, using a 5/16 in. (8 mm) hex key, unscrew the oil cap (with the dipstick attached) and tilt the log splitter forwards to allow the oil to drain from the tank.
3. Tilt the log splitter up vertically and place a funnel into the drain hole. Then fill the hydraulic tank with new AW32 anti-wear hydraulic oil.
4. To check the oil level, wipe the dipstick with a cloth, and with the log splitter tilted vertically, insert the dipstick fully into the drain plug, then pull it back out. The oil residue should sit between the top notch indicating full oil level, and the bottom notch indicating low oil level.