This post may include affiliate links. If you make a purchase through these links, we'll receive a commission at no extra cost to you. This support helps us maintain and grow our site. Thank you for your support!

Changing hydraulic jack oil can be difficult, especially if you are new to it. How to change hydraulic jack oil?

A hydraulic jack is a very useful tool for lifting up heavy objects like cars and other vehicles. But if it runs out of oil, it can’t do the job.

To change the oil in a hydraulic jack, you simply open the release valve, get rid of any old oil that may have been inside and inject the new oil. Once you’ve closed the release valve, you check for the performance to make sure it’s working fine.

These steps seem easy enough, but can be a bit complicated for beginners to carry out. This is especially true if you have a floor jack.

Since we do change our jack oil quite frequently, we considered the easiest way to explain this process to beginners, and have collected this information in one place.

Table of Contents

Why Should You Change The Oil?

Hydraulic jacks can lift your heavy objects only if there is enough fluid inside them to move the piston back and forth. The oil is a vital part of the jack’s functionality, but over time the oil levels decrease. This causes the performance of the jack to go down as well, and you’d have to change the oil.

When to Change Hydraulic Jack Oil?

Ideally, you’d have observed the level of oil in the jack regularly or even how often you’ve used it, so you’d be able to tell that it’s time to change the oil. But not all of us can always be certain.

The performance of the jack itself will also let you know that it’s time to change the oil. For example, the ram starts showing resistance when you try lifting objects and becomes rather inefficient. In such cases, you should check the oil level to see whether it is time for a replacement.

What Oil Do You Need For A Hydraulic Jack?

You can’t actually use just any type of oil for your hydraulic jack. There are specific types of jack oil that you should use, but if you don’t have any on hand, you can opt for a replacement as long as it has the following qualities:

  • Fluidity at lower temperatures
  • Water tolerance
  • Thermal and oxidative stability
  • Cleanliness
  • Corrosion control
  • Anti-wear properties

Sometimes people use motor oil or brake oil for their jacks, but these oils have the wrong level of viscosity and are not useful for hydraulic jacks.

Changing the Oil In Your Hydraulic Jack

When the time to change the oil comes, the steps to follow are pretty simple. You’d need to have a screwdriver, a drain bucket and an oil gun dispenser on hand to go about the process effectively.

Bottle Jack

If you’re using a bottle jack, first you open the release valve. Any oil that is already inside may have become inefficient, either due to sludge or simply losing some of its lubricating properties. You need to remove the oil plug from the bottle jack and drain the oil in it. This is where you use the drain bucket.

Once you’ve removed any old oil, you take your jack oil and inject it into the oil plug with the help of an oil dispenser. Once you’ve finished injecting the new oil, you can simply put the oil plug back and close the release valve.

Make sure to pump the jack a few times to see if the oil is pumping smoothly through the hydraulic chamber.

Floor Jack

If you’re using a floor jack, you may have to use slightly different steps.

First, move the jack to a flatter surface so you can inspect it safely. When changing the oil, it is best to look out for any kind of wear and tear or damaged components. Unless your jack is in good condition, it is best not to use it.

First, open the release valve and get rid of any oil that may be inside the jack already.

Now, look for the filler port. This is usually clearly marked and labeled so it shouldn’t be hard to find, but different models may have it in different places. Remove the cap and place it somewhere safe so you don’t lose it. You may need a wrench to remove the cap since it’s pretty tight.

Take a funnel and place it in the opening of the port. You should hold it firmly so that the oil doesn’t spill out as you pour it in. Pour only until the indicated level. If you add too much or too little oil, the jack can end up malfunctioning. If you spill any oil on the jack itself, it is best to clean it immediately.

Put the cap back on the jack to make sure the oil doesn’t leak out. Don’t move the jack unless the cap has been secured tightly in its place.

Test the jack out a bit to make sure it’s working fine. Be sure to use the full range of motion when testing it out so you’d know immediately if there are any problems that need to be addressed.

The oil in a hydraulic jack doesn’t need to be changed that often. When you buy a new jack, the oil in it may even last up to two years at a time. After this, however, the oil will usually last about 12 months. It is best to make a habit out of checking the oil level to make sure it’s working fine.

After refilling, it is also good practice to bleed the cylinder a bit to tune the performance.

When storing the jack after a refill, make sure you do it in a way that avoids any oil leaking. You should also release the pressure on the jack before you put it away.

These steps may seem simple – and they are pretty simple – but you need to be careful when carrying them out to make sure your jack works smoothly.

How To Change Hydraulic Jack Oil (For Beginners)

About The Author

Matt Meurer

Matt Meurer

Matt is a VW Master Technician since 2009 after proceeding through the ranks as a Team Leader and Shop Foreman. He has developed software to increase car dealership efficiency, managed 10+ techs, and instructed students at multiple high-performance driving events since 2011. He is also the lead mechanic, engineer, and driver for Blue Goose Racing.

Read More About Matt Meurer