How to Replace the Cabin Filter in Your Lexus NX 300

Where the cabin filter sits and what it does

The cabin filter in your Lexus NX 300 cleans the air that flows through your heating, ventilation, and air conditioning system before it reaches the interior. Over time, it traps dust, pollen, mold spores, and other particles, which means it gets dirtier and restricts airflow. When that happens, your air conditioning and heating work harder, your windows fog more easily, and the air inside the car smells stale.

In the NX 300, the cabin filter is located behind the glove box on the passenger side. You do not need to remove the entire glove box — Lexus designed it to drop down partway so you can reach the filter housing without taking it apart completely.

Key Takeaways

The cabin filter sits behind the passenger-side glove box and should be checked every 15,000 miles or once a year, whichever comes first.
Replacing it takes about 10 to 15 minutes and requires no special tools beyond a screwdriver to release the glove box latch.
Lexus part number 87139-02090 is the OEM cabin filter for the NX 300, though aftermarket filters from other manufacturers fit the same housing.
The filter slides out horizontally and the new one slides in the same way — pay attention to the arrow on the frame, which shows the direction air should flow.

What you need before you start

Gather a new cabin filter before you begin. The OEM Lexus part is 87139-02090. If you choose an aftermarket filter, confirm the part number matches your model year and that it is sized for the NX 300 — filters from other Lexus models or other vehicles will not fit the housing.

You will also need a Phillips head screwdriver to release the glove box latch. Some people find it helpful to have a flashlight or headlamp so you can see inside the glove box cavity, though it is not required. Lay out a small cloth or newspaper underneath to catch any dust that falls when you remove the old filter.

Steps to remove the old filter

Open the glove box fully and look at the right side, where you will see a small latch or clip. This is what holds the glove box in the closed position. Use your Phillips screwdriver to release it — you may need to push or turn it slightly depending on your model year. Once released, the glove box will drop down on its hinges, giving you access to the filter housing behind it.

Look up into the cavity and you will see a rectangular plastic housing with a filter inside. The housing has two clips or tabs on either side. Press or pull these tabs inward to release the housing cover. The old filter will slide out horizontally toward you. Note the direction of the arrow printed on the filter frame — this shows which way air flows through it.

Before you install the new filter, take a moment to wipe out the housing with a dry cloth or vacuum it gently. Dust and debris collect in there over time, and cleaning it means the new filter starts fresh.

Installing the new filter

Check the arrow on the new filter frame and make sure it points in the same direction as the arrow on the old filter did. This matters — if the filter is installed backward, airflow is restricted and the filter does not work as designed. Slide the new filter into the housing horizontally, making sure it sits flat and fully inserted.

Once the filter is in place, close the housing cover by pressing the clips or tabs back into position until you hear or feel them click. The cover should sit flush with no gaps. Then push the glove box back up and re-engage the latch with your screwdriver. The glove box should close smoothly and stay in place.

How often to replace it

Lexus recommends checking the cabin filter every 15,000 miles or once a year, whichever comes first. In dusty environments or if you drive frequently on unpaved roads, you may need to replace it more often. If you notice that your air conditioning is not cooling as well as it used to, or if the air smells musty even after running the system for a few minutes, the filter may be clogged and ready for replacement before the scheduled interval.

Some drivers replace it every 12,000 miles as preventive maintenance, while others go 20,000 miles or more if they drive in clean conditions. Checking it yourself takes only a few minutes — if it looks dark or clogged when you open the housing, replace it. If it still looks relatively clean, you can wait.

OEM versus aftermarket filters

The genuine Lexus filter (part 87139-02090) is made to Lexus specifications and fits the housing precisely. Aftermarket brands like Bosch, Mann-Filter, and others make cabin filters for the NX 300 that fit the same housing and perform similarly. The main difference is price — OEM filters typically cost more, while aftermarket options are usually cheaper.

Both types work well if you buy the correct part number for your model year. The housing does not care whether the filter inside is OEM or aftermarket — it only matters that the filter is the right size and the arrow points the correct direction. If you are unsure which aftermarket filter fits your NX 300, check the part number against your vehicle's year and trim level before ordering.

Frequently Asked Questions

Can I drive with a dirty cabin filter?

Yes, but your air conditioning and heating will not work as well, and the air inside the car will smell stale or musty. A clogged filter also makes your climate control system work harder, which uses more fuel. Replacing it restores normal airflow and keeps the interior air fresher.

What if the glove box latch is stuck?

Try spraying a small amount of penetrating oil around the latch and letting it sit for a few minutes. Then gently work the screwdriver back and forth to loosen it. If it remains stuck, you may need to remove the glove box entirely, which requires removing a few more fasteners — consult your owner's manual for the exact steps.

Does the cabin filter affect engine performance?

No. The cabin filter only cleans air that enters the passenger compartment through the climate control system. The engine air filter is separate and located elsewhere under the hood. A dirty cabin filter will not affect how your engine runs, only the quality of air inside the car.

Can I clean the old filter instead of replacing it?

You can vacuum or gently tap it to remove loose dust, which may restore some airflow temporarily. However, once a filter is saturated with particles, cleaning does not restore it to like-new condition. Replacement is the better choice for consistent performance and air quality.

How do I know which direction the arrow should point?

The arrow on the filter frame always points in the direction that air flows through it — toward the passenger compartment. When you remove the old filter, note which way its arrow points. Install the new filter so the arrow points the same direction. If you forget, the arrow on the housing or in your owner's manual will show you the correct orientation.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.