Should You Pre Fill An Oil Filter [Explained]

Should you pre fill an oil filter? This question will appear in your mind if any of your friends fill the filter before installing it. 

Well, it depends on the position of your oil filter on the vehicle. If the filter fits vertically, you can surely try to pour oil into the filter before screwing the filter on your car. On the other hand, we don’t recommend you pre-fill the oil filter if the filter sets horizontally. 

Besides disclosing the answer to that question, we will also describe:

  • How to pre fill oil filter properly?
  • Why should you not fill the oil filter before installing it?

So, stay with us till the end of this guide to explore every answer to those questions. 

Should You Pre Fill An Oil Filter?

You can pre-fill the oil filter if it sets vertically, easy to pour oil and let you screw it on without spilling. On the other hand, if the filter fits horizontally, you shouldn’t pre-fill your oil filter.

All the oil will just pour out when you start to screw on the horizontal oil filter. And you don’t like to make a gigantic mess, do you?  

Now, let’s break down the question from another perspective, based on the engine type. 

For most passenger cars, we don’t think it’s essential to pre-fill the oil filter and it wouldn’t hurt the engine. In contrast, for larger vehicles like trucks, the oil filter itself holds a lot of oil.

When you drain the oil completely, there will be no oil in the filter for lubrication. If you add oil after changing the oil filter, it may take a bit more time to supply the oil into the engine, which may damage the engine. So, pre-filling the filter, in this case, will be the safe side. 

In short, it depends on where the oil filter is set and the engine you have that will determine whether you can pre-fill the oil filter or not.

If you have a passenger car or a large truck and the oil filter fits vertically, you can fill the filter before installing it. Otherwise, you can’t pre-fill the oil filter without spilling if the filter sets horizontally. 

How To Pre-Fill Oil Filter?

Pre-filling the oil filter is the same as changing the oil and oil filter normally. The only difference is you need to pour oil into the filter before installing it if you wish to pre-fill the filter. Below, we will show you the exact way we pre-fill the filter. 

Equipment You Need:

Make sure you have the following equipment at your fingertips: 

  • A high-quality engine oil. We recommend you choose the oil according to the car manual.
  • An oil filter. 
  • A funnel that helps you pour the oil without a spill. 
  • A pan or bucket. 

Drain The Oil And Screw-Out The Filter

Now, follow the below steps:

  • Jack up your car and go underneath your car.
  • Use a screwdriver to remove the access panel to access the drain plug and oil filter. 
  • Now, line up the oil catch pan or a bucket right underneath the drain plug. Then, remove the drain plug to pour the oil.
  • Once you drain all the oil, put back the drain plug into its place. 
  • Next, screw out the oil filter. 

Pre-Fill The Oil Filter And Install It

After uninstalling the old oil filter, it’s time to screw on the new filter. Before installing the filter, fill it with oil. You can use a funnel to prevent oil spills. Now, install the oil filter carefully (so that the oil wouldn’t pour out) into its place.

Why Not Fill Oil Filter Before Installing It?

Though it’s possible to pre-fill the oil filter if the filter is in a vertical position, we don’t recommend you fill the filter before installing.

Our experience says that the oil will spill out through the filter that fits vertically on your car. We found oil everywhere and struggled to screw on the filter. 

On top of this, pre-filling the oil filter will bring no significant benefits. It only takes a second or two for the oil pressure to build up and fill the oil filter. Indeed, it doesn’t hurt your engine if you fill the oil filter after replacing it. 

And of course, no car manufacturer says you need to pre-fill the oil filter. If filling your engine after installing the filter will damage the engine, the manual surely recommends to pre-fill the oil filter. So, you don’t need to worry about anything if you fill the oil filter after changing it. 

Conclusion

We hope you get the answer to your question: Should You Pre-fill an Oil Filter? 

You can surely try to pre-fill the oil filter if the filter fits vertically on your car. Otherwise, we don’t recommend you fill the oil filter before installing it if the filter fits horizontally. 

Turns out, the oil will spill out despite having a vertically positioned oil filter. So, it’s better to fill the oil after installing the oil filter. 

About John M

John contributed as a technical head at an automobile company just 2 years after his post-graduation in Automobile Engineering. He loves to lead a free life, so he left his job & started blogging. Now, he does research on every automotive problem, part & product and seeks a better solution & best products & shares his findings with his readers to help them as well as to minimize their struggle.

Leave a Comment