K&N Air Filters

I've run K&N filters for 20 plus years. Mostly in turbo applications. In a vehicle like the 9, the only gains you will feel is in the pocket book. Over time, you won't be throwing filters in the landfill. Not sure about long term land impact, I left that back in my '07 Hybrid escape awd days. On my K04 turbo Passat there were HP/MPG gains at WOT
 
K&N filters help the engine "breathe" better and faster.
You don't necessarily see gain in static hp or torque, or MPG.
However, you can feel the rev responses of engine. If you can't feel the difference,
it is a waste of money for you definitely.
Obviously, engines with superchargers or turbos are even better fit for K&N-type of filters.

Yes, more dirts might go thru, but is that worse enough to hurt the engines?
My answer is no. I have been running it since new. My OE filter is my backup filter when I had to clean the
K&N filter and need to wait for it to dry. I can feel the difference every time I had to use the OE filter.

If you drive slowly, calmly and peacefully, you do not need K&N filters. They are for people who
enjoy a bit of spirited driving. Just MY humble opinion.
 
A lot of small differences could be argued to have long-term impact w/o solid data.
If you worry about it, don't use it.

I am perfectly fine with K&N filters, and will continue to use them.
Those who had issues either don't re-oil them, or over-oiled them.
 
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K&N filters breath better because the holes in the material are bigger. Its been proven. although oiling the filter makes dirt stick to the filter more, once that oil is depleted you are letting more dirt in. You can put as much oil on it as you want, but in the end you'll be letting bigger contaminating particles into your intake. Have you ever put a flashlight behind one? (boom06)

There are lots of opinions out there, but K&N filters are for racing where engines are torn down or replaced frequently. They are not engineered to make your engine last long like normal filters are. The only thing I've noticed in the past is dirtier oil. I don't use them.

The K&N air filter threads are as bad as the "which oil to use" threads. Here's a good experiment and it even references a Mazda filter. The results are interesting, especially for the Amsoil filter:
http://www.bobistheoilguy.com/airfilter/airtest3.htm


 
K&N is garbage. No real gain and to be honest I have seen how these can ruin motors. Once the oil in the filter picks up the dirt it usually falls out in the box or clogs the filter. The area where the oil has picked up the dirt and has fallen out of the filter has left a large enough area for micro particles to enter the engine. Sure the oil and filter can help take care of that but to be honest I rather have nothing entering my engine. Stick with OEM filters and change them accordingly. For the possible 1/16 hp gain from a filter is concerned, I rather have a true filter in place. I have a SAE Test somewhere showing that K&N is terrible at filtering over paper. Sure it lets in more air but like I said, you want a little more HP or a Clean motor that will last a long time. Stay away from those things.
 
I bet you that on every auto forum, there is a K&N thread somewhere....

Saw one on the PriusChat.com also. Go figure.
And, most of them are very very long......
 
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There is. They are making money off fooling customers with clever advertising. Don't fall for it. Stick with OEM.

here is one to read up on:
http://www.gm-diesel.com/vbull/upgrades-and-aftermarkets/1128-air-filters-k-and-ns-reply-rumors.html

and another one with extensive testing showing K&N to be the worst in filtering.

http://blog.consumerpla.net/

Up to you though. iF you think cleaning and oiling a filter every time is fun and you get something like some HP out of it, go for it. Otherwise its much easier and cheaper in the long run to use OEM paper filters or if you want something performance and something you can clean and reuse, go with the German made 3 layer foam filters which work well.
 
Let's just agree that some people are really for them, and some people are really against them, with good arguments on both sides. Neither side is gonna convince the other. Agreed?
 
True and the ones for them are uninformed consumers. With just a little research on the product you can see it's not all it's cracked up to be.
I don't think there is any arguing per say going on here. Just stating some facts. As I mentioned as well I have seen the SAE Test on these filters and how bad they actually filter. You can make up your own mind. I am just trying help save headaches for those who want to keep this car for a long time.
 
True and the ones for them are uninformed consumers. With just a little research on the product you can see it's not all it's cracked up to be.
I don't think there is any arguing per say going on here. Just stating some facts. As I mentioned as well I have seen the SAE Test on these filters and how bad they actually filter. You can make up your own mind. I am just trying help save headaches for those who want to keep this car for a long time.

Wow! That's a bold statement. I and many other "enthusiasts" have used these filters for years in various cars, and have had no ill effect. They certainly would not have gained the popularity that they have if they were destroying engines after all these years. The truth is that people who don't take care of them have the issues. Those same people probably wouldn't change the paper filter often enough, and have issues there anyway. Don't judge people here just because you don't like something.

From K7N's warranty page:
ENGINE PROTECTION LIMITED WARRANTY
Unlike many companies, our warranty for O/E replacement air filters and intake systems does extend beyond the replacement of a defective K&N part. For the original purchaser of the product, our warranty covers any engine damage or related costs incurred as a direct result of the use of a properly installed and maintained K&N O/E automotive replacement air filter or intake system on the specific vehicle for which the product was designed to be used by K&N. This includes reasonable vehicle repair costs directly related to an engine problem caused by the failure of a K&N product. Furthermore, we warrant that using our product will not result in a vehicle warranty denial. K&N will not be responsible for any indirect, consequential, special, contingent, or other damages not listed above.


So if your claims are correct, they'd cover any damage due to their filter not properly filtering.
 
I would like to quote an interesting statement I found on the web:

"There are two kinds of opinions in this world: Mine or the wrong ones."
 
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I have investigated K&N filters for years on higher performance cars that are run on dynos. My findings? They don't do anything substantial on stock engines. 0.5% generally and once they get dirty enough, usually six months of typical environment, the 0.5% gain is gone.
 
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Head-desk-1.jpg
 
I've heard of guys having problems with their MAF sensors fouling up and throwing codes, shortly after they installed an oiled filter like K&N. This is on another forum I frequent, not here. It isn't widespread, but it happens. I believe the fix is just to wipe the sensor down. I don't know much about the CX-9 motor yet, but I assume the potential is there for a similar reaction?

On my last truck (dodge ram hemi), I had a K&N cone filter on it, that I cleaned and oiled pretty regularly. After about a year or so of having it, my truck would randomly spit and sputter and go into limp mode. Turning it off/on would temporarily fix it. Then it started happening too frequently. Had the codes checked, it was something to do with the throttle body. Had the throttle body replaced, had no more issues. I suppose a theory could be that the oil was gunking up the TB? I didn't care, because I sold the truck 6 months later before the transmission went (peep)

I'm not going to take a side on performance gains or not, because I just don't know.

I will probably try to keep OEM air filters in this CX-9.
 
Transmission went on a Dodge truck?? shocker!!

1st place: dodge truck transmission failures
2nd place: chrysler products burning to the ground

Won't you buy one?
 

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