What's a Cabin Air Filter?Cabin air filters (sometimes referred to as pollen filters or A/C filters) are used to trap dust, pollen and other small particles before they enter a vehicle's heating and A/C system. Not all trucks have cabin air filters, but they are installed in many newer pickups, especially higher-end models.
When heat or A/C controls are set to bring in fresh (outside) air, the air passes through the cabin filter before it can enter the blower, eliminating a portion of the gunk that would otherwise float around inside the truck. Cabin filters don't remove everything from the air, but they definitely make the interior more breathable, especially for people who suffer from (some types of) allergies or are sensitive to dust.
When Should I Change the Cabin Filter?Like any air filter, a cabin filter that's doing its job gets dirty. Reduced air flow is annoying when you want to use the heat or A/C, and could eventually damage the truck's blower motor if the problem isn't corrected.
Cabin air filters aren't all located in the same place, but the most common installation areas are either inside the truck (behind the glove box) or under the hood at the base of the windshield. Your owner's manual should show you where to find the filter and normally explains the steps required to replace it. The truck's maintenance schedule probably suggests time intervals for filter changes, but consider them a basic guide -- someone who regularly drives on gravel or dirt roads will need to replace the cabin filter more often than a person who's always on a paved highway.
Checking a cabin filter for dirt differs from the glance you'd take to determine if the engine air filter should be replaced. A cabin air filter traps very fine particles, so you'll need to take a close look at the bottom of the folds (see the photo above). If you see a fair amount of discoloration or dust, it's time for a replacement.
Click on the photo for a full-size view of the dirty vs. clean cabin filter .
Is it Okay to Clean the Filter and Reinstall It?Do not try to blow the filter out and reuse it:
- Compressed air opens up the filter's fibers -- it will no longer trap particles.
- Do you really want to blow all of that dust and pollen into the air where you are likely to breathe it in?
The next time you walk towards your truck after it's been sitting for awhile, and see that its paint is tinged yellow from pollen (or light brown from dust), remember the cabin air filter. It's keeping the stuff you see on the outside of the truck from coming inside for a ride.