How often do you change your Air Filter?

[mountainwalker]

How often do you change your air filter? If your air filter isn’t that dirty after 6 months, would you still change it? Since it’s a very inexpensive part ordered online, does changing it more often offer real performance benefits, even when not significantly dirty? I tend to change more often, just curious if this is really helpful. This is for a 2003 Outback VDC 3.0L H6 in excellent condition, 105,466 miles.

[AWDfreak]

My air filter gets dirty fast, even though I don't live in a dusty area.

 

I would say, I change mine about once every 1 to 2 years.

 

I believe the interval Subaru sets is either 15,000 miles or 30,000 miles for the air filter.

[porcupine73]

Generally I replace once per year, which is around 8,000 to 12,000 miles. Supposedly they actually get a little better at catching dirt after they're slightly dirty. Waiting too long can make it more restrictive to airflow, which can then reduce economy because of the pumping losses.

[davebugs]

I go 20k to 40k depending on the car.

 

I check them every 10k when changing oil (and usually rotating tires at 10k too). I "flip it" end for end to lets say find a cleaner surface. All airboxes cause the airflow into the filter to not be evenly distributed. This will start to leave a dirt mark you can see.

 

So often it gets one flip at 10k and changed at 20k, sometimes it lasts 30-40k.

 

I forget the ratio on how bad a dirty air filter can hurt mileage due to the ratio of air vs. fuel in the combustion chamber.

 

Often neglected, easily changed.

[bheinen74]

Every time i buy a Subaru, it gets:

New air filter, immediate oil and filter change, and usually new plugs.

Add to that new wiper blades, new hoses and belts, and usually a new battery. Also, usually install new tires.

 

Then like in 18-20k I will put in new air filter.

Edited January 4, 2012 by bheinen74

[danbennett2u]

Dont remember when I changed mine last. I usually pull it out and bang the dust out of it and throw it back in lol. I know thats not good but I don't care anymore. As long as air can pass. Will go back to changing it once every year or two once I replace my car with something younger.

[davebugs]

I write on airbox with chalk mileage of last replacement. Then every time I'm changing the oil I don't have to run to the computer to see how it's due. Try and find cheap chalk like at a dollar store. On seriousely a chunk of "innards" from drywall/sheet rock depanding on what it's called locally.

 

I usually have one ahead for all my vehicles - just like oil filter and oil which I stock more heavily.

 

Air & fuel filters, transmission and radiator are the forgotten maintenance items.

 

But the air filter has the shortest service life.

[Rooster2]

I check mine in the Fall when doing antifreeze swap out. Sometimes, after a year it still looks like new, so I just reinstall it. I am lucky to put 10K miles on my Subie per year, so for me an air filter lasts a long time.

[mountainwalker]

I "flip it" end for end to lets say find a cleaner surface. All airboxes cause the airflow into the filter to not be evenly distributed. This will start to leave a dirt mark you can see.

 

davebugs thanks that's a good idea - I do see an uneven distribution and will flip it. Someone on another forum also recommended holding the filter up to the light and if you can't see through it at all, might be time for a change.

[mountainwalker]

I'll also bang the dust and debris out of it.

 

Thanks for all the good suggestions.