Aftermarket Air Filters worth it?

[Lone Ridr]

I researched this subject 5 years ago when I was deciding whether or not to install a K&N on my Tacoma. Independent tests show that K&N air filters allow more dirt and dust to pass through with more air than standard paper filters. Particles 5 microns in size can pass through the filter. This “particle scouring” can lead to engine wear. I decided not to use one. It could lead to less carbon buildup on the back of the valves (last sentence, just joking).

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[kevinmccune]

I have K&N filters in all 3 of our older vehicles. They have between 180 and 250,000 miles and burn little/no oil.

Cleaning and re-oiling them is straight-forward:
1) Spray cleaner on, rinse off.
2) Let air dry (no compressed air, etc.).
3) Spray oil on, reinstall.

Drying can be sped up by setting the filter in front of a fan.

The K&N (and similar) vs OEM (and aftermarket) debate is right up there with engine oil, filters, and change intervals. People on both sides can find evidence to support their position.

You can't go wrong with the OE air filter. The downsides are long term cost and a potential minor reduction in performance.

I used K&N primarily because my wife and I were driving ~40,000 miles per year, and K&N saved us money. Also, with the red oil it was easy to see when they were getting dirty, and cleaning and re-oiling was quick and easy.

That said, the Badlands still has the OE filter. In a few days it'll be 4 years old and it has <8,000 miles on it! So buying a K&N makes less sense. At the rate we're going the factory filter will last 10 years or more.

WRT efficiency vs restriction, all else equal the more efficient filter will be more restrictive, however total surface area (number of pleats in a paper filter) can vary a lot. A filter with more area can be both more efficient and less restrictive.

One last thought -- if a person lives on a dirt road, or otherwise dusty area, and they are replacing paper filters frequently, the K&N .may make more sense.

you are right about the horrendous cost of OE filters these days,one thing to remember is particles that are few between and small enough have little effect on an ICE other than a polishing effect( well documented,I suspect filters like the "K&N" would come into their own during a dust storm or volcanic eruption.

 

[sajohnson]

you are right about the horrendous cost of OE filters these days,one thing to remember is particles that are few between and small enough have little effect on an ICE other than a polishing effect( well documented,I suspect filters like the "K&N" would come into their own during a dust storm or volcanic eruption.

A volcanic eruption is always a possibility.

I've been working on cars (as a hobby) for over 50 years. K&N filters are one of several recurring subjects. The opinions are always pretty polarized, from "A massive increase in hp and torque!" to "Will destroy your engine within 1,000 miles!"

I'm exaggerating of course. My sense is that they create little if any performance increase (and any improvement would be up toward redline when demand for air is the greatest) but if oiled properly they do not allow any engine damage in excess of what the OE filter allows.

There are probably millions of opinions and anecdotal experiences with K&N filters. FWIW, I have 3 vehicles with 180-250,000 miles on them using K&N and they all run great and burn very little oil.

 

[sajohnson]

More than most of us want to know:
https://pmc.ncbi.nlm.nih.gov/articles/PMC7475895/

Experimental Study of Filtration Materials Used in the Car Air Intake
Quote:

"The manufacturers of filter media using nanofibers have developed proprietary technologies, e.g., Ultra-Web® and Fibra-Web® by Donaldson Company Inc. Minneapolis, MN, USA Finetex MatsTM by Finetex Technology Inc., USA and AMSOIL Ea Air Filters, USA and Canada." [45]

It's a l-o-n-g article but there is a lot of good info. You can skip down to the charts and graphs, and the conclusion.

Unfortunately, they do not name specific filter mfrs (except for above) and models, but they do say which type of filtration media is best, which might be helpful. Hint: they like nanofibers, but they do load up quicker (shorter service life).

 

[Chops]

Oil Geek discusses air filters with a Filter Geek. Filter Geeks states most folks change them too early.

 

[sajohnson]

Oil Geek discusses air filters with a Filter Geek. Filter Geeks states most folks change them too early.

Excellent video, thanks!

 

[Cancunbadlands]

K&N air filter is designed to fit exactly where your current paper filter sits. It uses oiled cotton gauze to improve airflow while maintaining high filtration standards.
You’ll likely never need to buy another filter for the life of the truck. K&N recommends cleaning it every 75,000 miles under normal highway driving conditions.
2024 2.0l ecoboost

 

[Meeka]

AFE makes a dry filter that i will be purchasing soon.

Pictures? Site? Thx.

 

[phantomfixer]

Are the aftermarket air filters ( high flows like K&N, green, specter, etc. ) really worth it? For those that did, was there any increase in performance/mileage? Or is OEM in the long run the best?

You can’t get a better filter than a Ford OEM.Anything else is just a waste of money

 

[sajohnson]

Regardless of which filter is used, it would be extremely helpful to have a differential pressure gauge.

As the video above and the article I linked to state, filters become more efficient as they load up with dirt. A visual inspection may indicate that a filter is dirty and needs to be replaced, when actually it is working at peak efficiency and should be left in place. The graphs in the article (scroll way down) show that very clearly.

Obviously, at some point a filter will become so loaded up with dust that it begins to get restrictive, but there is no way to determine that visually. Here are 2 gauges I found with a quick search. I'm not necessarily recommending either one, but they are examples of what's available:
https://www.summitracing.com/parts/wix-24801?
https://www.amazon.com/WIX-Filters-...0014BI1KA/ref=cm_cr_arp_d_product_top?ie=UTF8
https://www.amazon.com/85-2445-Filter-Minder-Push/dp/B000E5XQDY/

 

[jonshep]

I replaced mine yesterday. I replaced with an "epauto". Are they any good? I will find out.

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