I just bought an 05 F250 with the 5.4 and it came with a cold air intake. after reading this, I want to rip it out and put the OEM system back in.

 

I just changed my oil yesterday. Im going to send in my oil to get checked by black stone. Might try a dry filter too. I don't really wanna put my stock intake back on but I will if it means protecting my motor. The next time I have to change my oil I'll send it in again to get it analyzed to see the difference. I'll know if my investment was worth it or not.

 

I just bought a 93 Vette,I saw a K&N sticker on the fan shroud.Due to work & crappy weather I havent had a chance to check it out,if it does Im trashen it.
My old 85 Vette &90 had a MAF sensor so I wouldn't even think of a oil impregnated air filter,Just my 1/2 cent input.

Component disassembly to reach the mass airflow sensor (MAF).
Mass airflow (MAF) sensor problems on these engines typically cause lean fuel conditions and possibly hard starting or even no starts. If the sensor element becomes contaminated with dirt, fuel varnish or oil (from oiled aftermarket low restriction air filters), the sensor won’t read accurately. MAF sensors can often be cleaned with aerosol electronics cleaner.

 

Walking through the local Walmart's Auto section. They recently changed the department around and I was making sure they still had the MC filters. This is what they replaced on the shelf that use to have the MC Oil Filters. They have the whole top shelf loaded with K&N Filters. Those for from what I can tell are Ford applications had the Ford Racing logo.





Either way in work, one of my co workers swear by K&N filters. He said it has been the only thing that gets the best mileage and he has seen any where between 2-5 MPG on any vehicle he used the filters on. I said they might work but I would not trust them as they could cause problems for the engine down the road. The same co worker was even trying to get management to get on board with the filter saying it would save the company money in fuel costs.

 

If you throw all the science aside, the 3rd party ISO certified testing facility docs in the trash, I can tell you about my own personal experience in regards to K&N's warranty....of which they do not honor....this dates back to 1997 and my own personal OASIS documented experience with K&N.... I installed an oem replacement unit on our new 1997 Cougar Sport (1 week old, factory special order), the filter was purchased directly from K&N. For those who may not know, the Cougar Sport is essentially a mustang GT with 4-wheel independent suspension except it is built on the MN12 chassis (LSC Coupe) which gives extra stiffness. Within 90 days, multiple intake location specific sensors (paraphrasing here) went bad...throwing codes. After Ford verified and replaced under warranty twice the sensors during this period, when they analyized the parts, they determined oil residue from the K&N caused the component failure. Ford recommended the filter (K&N) be removed...and there has been no other failures to date (2017) on these components (20 years later).

I called K&N and advised them (very nicely) of the issue....back then the K&N filter was around $60 iirr......they stated if you are not happy with the filter and have the original box we will take it back and refund the $. Even with full documentation, K&N never (including multiple visits with their staff at their offices and at conference meetings) would ever take any action and just kept insisting there must be another cause for this with the car...there wasn't. K&N has made repeated references throughout the years on multiple chat sites that this situation has never occurred, yet the oasis documentation is very well established.

 

Use at your own risk. I've had my K&N on my 6.7 diesel for over a year. I installed it wanting a little bit more HP while towing. I got what I purchased it for. There are people saying the filters are junk and allow more dirt into the motor. I have no evidence of this in regards to my truck. I only have 1 oil change on my filter. I sent a sample to blackstone lab. Everything came back normal. I did have a few CEL. Always the same code. I can't remember the number, but it was a difference in air pressure psi between the map and the mas. Its amazing that any air gets into the shock air box. When I installed the K&N I took off massive amounts of plastic. With the K&N now my truck can breath. The CEL was traced to the air filter... it was over lubed. I cleaned the sensors and haven't had any issues. K&N wasn't my top pick but I didn't have a lot of options. I don't live in a free state... I have to get my 2011 diesel truck smoged every year to pay for my registration. In this state you need a CARB compliant air intake. It was on sale, out the door just over 200.
If you gonna just it i suggest using a dry filter and getting your oil tested.

 

I have been a K&N user for over 30 years... Yes oil-film can cover sensors...

I now run the AEM oil-less washable air filter... very well made.
over 1 year now.
Look into it.

 

I just find it interesting that people had issues with the K&N filter. However, I don't know how to take it this as Ford is giving what appears to be applied consent to using the filter with Ford products. Ford like any manufacturer is trying to lower their after sales cost (warranty) Does this mean if the dealer tech performing a warranty service to a vehicle finds this filter in the air box he or she is OKing it as not being the problem? Are they still going to deny the claim since there was an "aftermarket" component that may or may not have caused the original trouble? I see a slippery slope here as if Ford could deny for aftermarket even though the clearly place their Racing logo on the product.

 

I have used K&N's for many years now. The main reason is economics. There are some over oiling issues but once you figure out how to clean and re-oil them the problems go away.

I keep a paper filter to swap in and will actually wait a couple of days after I clean and re-oil. Letting it soak in and dry is the key.

 

I am not an authority on this, but will add my two cents. Back in the old, old days motor vehicles came from the factory with oil bath filters. They were standard equipment up until about 1959. Despite the convenience of the paper air filter cartridge, the oil bath system is proven to be far more efficient when it comes to particulate removal. Its demise was due the fact that draining, cleaning and refilling were no where near as convenient as swapping out a paper filter cartridge.

 

Common sense will tell you that if the filter is less restrictive, you get better airflow. More air passing the filter element, allows for more contaminants. With an oiled filter, you are trusting the oil to trap particulate contaminants, as air passes.

Myself, and many others, have used K&N oiled filters for decades. Mostly with success. Occasionally, somebody adds too much oil to the filter.

Whether you get performance or mileage gains is debatable. Obviously, when you change a part from OEM specs, not everything stays the same. But is it enough of a difference? Sometimes, that depends on the car. Unbelievable, but true, that there are instances of mileage improvement. As for performance, it's nothing that you will actually feel, or win a race with.

With the numbers on an engine dyno, there may be a minute change. Run an engine, just the engine, on an engine dyno, and measure the power output. The change will be so small, that it will not translate to that engine mounted in a car, and actually adding more power to the wheels on the road. But, it's there. And if you are bolting on accessories, an intake or oiled filter is something that goes right along with all of the other bolt on accessories. Don't forget the stickers that came in the box. Stickers not only add HP & torque, they intimidate the competition, and draw the attention of the police.

 

Another reason Not to get an K & N filter:

If you drive through a water puddle in a heavy down pour and water gets sucked into your air intake, a foam filter will allow that huge gulp of water Right through where a paper element filter will sift that water gulp more.
So if you don’t want your engine hydro lock grenade ruined more easily, stay away from foam filters!

Plus come on, it’s like returning to the Stone Age, a filter you spend hours carefully washing and drying and oiling just the right amount... we pay extra money for all that hassle for what!?
The regular filters are fairly reusable cleanable, just get our your vacuum and crevice tool.

Take care

 

I get your point with the water. However I've never experienced my filter getting wet. I could see it getting wet if I sink my truck up to the filter. Also they do make oil less filters. Im still running mine. I've been getting my oil tested by blackstone the last 60k I've had it installed. No increase in dirt or other things going into my motor.

 

I might as throw in my 2 cents as well! Unless you are talking about a system that was specifically designed for a specific application there are very little hp/tq gains actually achieved in a street use vehicle and there are very few docs that these mfg’s can produce that actually show an increase in hp/tq in the power-band range of a relatively stock street vehicle (IMHO). While oil applied filters they have their purpose in off-road applications, Ford/GM/Dodge all have “watch-out” bulletins where the oil has contaminated intake sensors. - they even have a training video for the techs on this (flatratetech.com), but lets talk about performance for a minute...…

If you look at the flow data, WIX HP filters flow 98+% of K&N and have a much smoother flow post filter plus excellent filtering, for a fraction of the price! Testand Corporation conducted an ISO standards test on automotive air filters which can be viewed at this link: http://www.dieselbombers.com/chevrol...r-testing.html.

“After only 24 minutes the K&N had accumulated 221gms of dirt but passed 7.0gms. Compared to the AC, the K&N “plugged up” nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt.”

A Ford MasterTech made this video which talks directly about the aftermarket CAI’s.....QA of engineering and design is a big issue:



Let's talk about their warranty...… and my own personal OASIS documented experience with K&N....

I installed an oem replacement unit on our new 1997 Cougar Sport (1 week old, factory special order), the filter was purchased directly from K&N. For those who may not know, the Cougar Sport is essentially a mustang GT with 4-wheel independent suspension except it is built on the MN12 chassis (LSC Coupe) which gives extra stiffness. Within 90 days, multiple intake location specific sensors (paraphrasing here) went bad...throwing codes. After Ford verified and replaced under warranty twice the sensors during this period, when they analyized the parts, they determined oil residue from the K&N caused the component failure. Ford recommended the filter (K&N) be removed...and there has been no other failures to date (2020) on these components (23 years later).

I called K&N and advised them (very nicely) of the issue....back then the K&N filter was around $60 iirr......they stated if you are not happy with the filter and have the original box we will take it back and refund the $. Even with full documentation, K&N never (including multiple visits with their staff at their offices and at conference meetings) would ever take any action and just kept insisting there must be another cause for this with the car...there wasn't. K&N has made repeated references throughout the years on multiple chat sites that this situation has never occurred, yet the oasis documentation is very well established.

If I may quote Arlen Spicer, a well known engineer who conducted a very broad SAE standards test on aftermarket filters.....

“Now that I am not doing the tests and my objectivity is not necessary, let me explain my motivation. The reason I started this crusade was that I was seeing people spend a lot of money on aftermarket filters based on the word of a salesperson or based on the misleading, incomplete or outright deceiving information printed on boxes and in sales literature.

Others are persuaded by the claims of aftermarket manufacturers that their filters filter dirt "better than any other filter on the market." Sounds very enticing...….. Spending $1500 to test a filter sounds like a lot. But if you were a filter manufacturer and you believed your filter could filter dirt better than any other media on the market, wouldn't you want to prove it? ……….. So why don't these manufacturers do this? Hmmm?

Now I am not saying that ALL aftermarket filters are useless. A paper filter does not do well if directly wetted or muddy. It may collapse. This is why many off-road filters are foam. It is a compromise between filtering efficiency and protection from a collapsed filter. Now how many of our trucks collapse their filters from mud and water? However, if a filter is using "better airflow" as their marketing tool, remember this....Does it flow better? At very high airflow volumes, probably. BUT, Our trucks CAN'T flow that much air unless super-modified, so what is the point? The stock filter will flow MORE THAN ENOUGH AIR to give you ALL THE HORSEPOWER the engine has to give. And this remains true until the filter is dirty enough to trip the air filter life indicator. At that point performance will decline somewhat. Replace the filter and get on with it. "

Ok, I'm done

 

Most cars have filters located very high. It would take a lot to get water to that level.