Repost from Fresh Ideas Blog

Cartridge oil filters are everywhere! Their use in modern vehicles was once strictly European– commonly found in BMW, VW, Audi, and Mercedes-Benz cars. Fast-forward to 2022 and you’ll find them used in several United States domestic and Japanese domestic makes and models as well. While there are still holdouts, many automakers have transitioned to cartridge oil filters for a variety of applications. Ford’s turbocharged 2.7L and 3.0L engines are good examples. Chrysler’s Pentastar V6 is another notable example that uses a cartridge oil filter. Even Toyota has joined the cartridge filter party.

Cartridge Oil Filter Market Continues to Grow

There are a variety of reasons for the resurgence of cartridge oil filters, which we’ve discussed in the past but in short, they all come back to climate fears. Many believe that this is because a filter made without metal is more environmentally friendly when disposed of. While that’s true and is certainly a part of the equation, the big picture is more complex. The major reason for the shift is that cartridge oil filters allow engineers to configure engines differently, helping to solve a variety of problems that aggressive climate legislation has created for efficiency and power output. As climate change comes into greater focus over time, the need for efficient engines and creative design solutions will intensify which subsequently means: more cartridge oil filters. That’s not a bad thing when you consider that they’re usually easier to remove and much less messy than a spin-on canister.


Easy removal of cartridge oil filters is a great benefit, but there are pitfalls installers should be aware of.  Some can be very complex, but even the most basic cartridge filters come with multiple components in the box. The extra pieces increase the chance of human error and make cartridge oil filters more prone to installation woes. Here are a few of the most common missteps that installers should try to avoid:

Misplaced O-rings

Misplaced O-rings are the most common misstep with cartridge oil filter replacements gone wrong. Most cartridge oil filter kits consist of the filter element and two O-rings– one large and one small. These O-rings need to be replaced with every oil change and there is a specific groove on the oil filter housing cap where the large O-ring is supposed to sit. Sometimes this O-ring is mistakenly placed into one of the cap threads rather than the correct groove. When this happens, the cap doesn’t seal properly with the housing when tightened, allowing oil to seep or spray out when under pressure. In addition to the engine’s mechanical issues that can result from oil starvation or oil pressure fluctuations, this scenario will result in a slick mess in the engine bay and could damage other components depending on the location of the oil filter housing. Always make sure that the O-ring is in the correct groove.

n20 oil filter housing cap that leaked

Accidental Removal of the Oil Filter Center Tube

The center tube of an oil filter, whether of the cartridge variety or spin-on canister type, is a critical part of the filtration process. In the case of cartridge oil filters, the center tube looks like a plastic, cage-like assembly that is attached to the inside of the filter cap. The assembly serves two purposes: The first is to give support to the flexible filter media when the filter is under pressure. The second, is to prevent oil from flowing right back into the sump rather than circulated through the engine as it should. This tube is not supposed to be removed from the cap during oil change service and as you can imagine, if it comes out with the old filter, failure to re-install can wreak havoc on an engine. Without the center tube, the filter will collapse under pressure and lead to oil pressure problems that could make the dash warning system look like a Christmas tree. It’s likely that the camshaft position sensor and variable valve timing will be affected, and the vehicle will run terribly.

another BMW oil filter that is missing the center tube
screenshot explains the consequences of failure to replace cartridge oil filter center tube

Failure to Replace the Center Tube O-ring

This is another one that highlights the importance of the center tube. When changing the oil filter, it may be tempting to reuse the small O-ring on the end of the center tube if it looks like it’s still in good shape. Please DON’T DO IT! These nitrile O-rings are only meant to last for one oil change interval because after repeated exposure to extreme heat, nitrile loses its elasticity and begins to break down. If this O-ring fails when the engine is in operation, some oil will flow back to the sump rather than through the engine. This scenario could starve the engine of enough oil to cause internal damage. We know that the tiny O-ring can sometimes be a pain in the neck to get off, but it’s not impossible with the right tools. An O-ring pick makes the job very easy.

cartridge oil filter cap diagram

Over-tightened OR UNDER-TIGHTENED Oil Filter Housing Cap

Cartridge oil filter housing caps are typically made of hardened plastic and are usually re-used from one oil change to the next. Over-tightening on re-installation can damage the threads,  result in cracks in the cap or pinching of the O-ring, all of which could cause leaks. On the other hand, an under-tightened cap may allow the oil pressure to push the gasket out and leak. Therefore, it is very important to follow the manufacturers’ torque recommendation for tightening the cap. The cap’s torque recommendation can usually be found in the vehicle owner’s manual and is often printed right on the top of the cap. For that purpose, Premium Guard has developed a preset torque socket that meets the most recommended torque specification of 25 Nm.

torque specification for a bmw oil filter cap


Just like oil filters, the housing caps come in a variety of shapes and sizes. In fact, it is estimated that there are over 70 different types of housing caps that are materially different. Using the right tool to remove and tighten the cap is of immense value to ensure the longevity of the cap. To that end, Premium Guard developed a tool set of 12 different cap wrenches that covers over 90% of applications with cartridge oil filters.

Make sure you have the right tool for the job.

WCSET14-01 oil filter cap wrench set with exclusive 25Nm preset torque socket

Premium Guard WCSET14-01 oil filter cap wrench set with compatibility