K&N filters

Lynnmor wrote:
I consider the use of oiled foam filters a total waste of money and a harmful product.

In no way what I am about to say is condoning the use of K&N filters as I do not use them. I've read the independent tests and will not use K&N on any of my vehicles.

Now, I may be taking your comment out of an assumed context, but you do know that OHV ATVs, Side-by-Sides and dirtbikes use oiled foam air filters and those vehicles are run in FAR WORSE dusty conditions than on-road vehicles. Heck, I just returned from a 6 day ATV riding trip in central CO and here is the result of 6 days of riding on an air filter. Picture is a comparison of my second cleaned and freshly identical air filter. This was from about 500 miles of trail riding. And yes, the oiled foam air filters do an excellent job filtering the air.

ktmrfs wrote:
some years ago an independent lab tested the factory duramax filter vs a large number of aftermarket filter systems including K&N and aftermarket direct replacement filters. This was done on the filter used initally on the duramax. Current duramax engines use a slightly different size and shape OEM filter. Haven't seen tests on the new filter.

The factory duramax filter was better at long term filtering, how much dust it took before restriction went above a certain defined limit, and how little dust made it through the fiter than the other filters including K&N. Often by a significant margin.

The "cost" of this is that the Duramax filter did have slightly more restriction than the aftermarket systems, fractions of a psi. Likewise for airflow for a given pressure drop. IMHO it was not significant.

IIRC the K&N wasn't the worst at letting dust through, there were others worse, but it was no where near as effective as the factory filter. And it took less dust to get to the point of needing cleaning.

How the K&N compares to other OEM filters who knows. But on my duramax's, the OEM is the only filter I wll use.

I remember that test and they did not test the whole filter, only cutouts of the filter media. In many cases, aftermarket intakes have filters with a much larger surface area than the OE. In the case of my truck, the ProGuard-7 filter in my intake has twice as much surface area as the stock filter. Also, the shape of the filter matters as well so only testing cutouts only tell part of the story.

some years ago an independent lab tested the factory duramax filter vs a large number of aftermarket filter systems including K&N and aftermarket direct replacement filters. This was done on the filter used initally on the duramax. Current duramax engines use a slightly different size and shape OEM filter. Haven't seen tests on the new filter.

The factory duramax filter was better at long term filtering, how much dust it took before restriction went above a certain defined limit, and how little dust made it through the fiter than the other filters including K&N. Often by a significant margin.

The "cost" of this is that the Duramax filter did have slightly more restriction than the aftermarket systems, fractions of a psi. Likewise for airflow for a given pressure drop. IMHO it was not significant.

IIRC the K&N wasn't the worst at letting dust through, there were others worse, but it was no where near as effective as the factory filter. And it took less dust to get to the point of needing cleaning.

How the K&N compares to other OEM filters who knows. But on my duramax's, the OEM is the only filter I wll use.

I've run K&N in my off-road and on-road vehicles for 20 years. To dispel the notion that they let huge amounts of dust through the filter, I have been putting a thin film of clear dielectric grease just past the filter on the intake tract. I clean it off with a white paper towel at every filter cleaning and have never seen a hint of dust or dirt on the paper towel. I like them and will continue running them. 3 of my K&N'd vehicles are over 250,000 miles without any engine issues.

Lynnmor wrote:

dodge guy wrote:

Colo Native wrote:

Terryallan wrote:
No. Didn't help a thing.

Not sure I want to waste $350. Thanks

$350?!!!! Not sure where you got that from? K&N`s go for around $50. You`ll never have to buy another. I have had a K&N kit on my V-10 X for 10 years and 80k miles and have no issues. really helps the engine breather in the mountains at higher RPM.

I also run K&N`s in all my other vehicles. Never an issue.

Increased air flow is only helpful at wide open throttle, during part throttle operation nothing has changed. If I had a truck that required full throttle to tow a trailer, I would rethink my choice of truck and not resort to band-aid fixes that will allow more dirt into the engine. I consider the use of oiled foam filters a total waste of money and a harmful product.

Just about any truck gas or diesel will see WOT in the mountains. So trying to say a truck is underpowered if it runs at WOT is ridiculous. And in 35 years of using K&N’s I’ve yet to have an issue as well as thousands of others. It’s not a “band aid” fix, rather a well thought out product! I consider throwing away $20 a year on filters a waste of money!

You can change from a paper factory filter to a K&N cleanable filter. The cleanable filters often pass air more when they are dirty than a clean stock paper filter.

Or can you add a different air intake. A diesel engine thrives on air and air out. Two of the best things you can do for a diesel engine is a new air intake and a 4 inch exhaust to reduce back pressure. I have gotten up to 23.8 mpg out of an F-350 with auto trans and a 7.3 l diesel.

Colo Native wrote:
I did forget to mention $350 is for the Cool air Intake system not just filter. Wish I could have seen this before now since it kinda derailed a little

I added the AFE pro 7 on my then new 5.9 Dodge/Cummins. Biggest benefit has been a 70-90 degree drop in EGT temps while towing. Boy the AFE's are very expensive compared to what I gave for my new AFE back then. I've done a oil analysis every 50k miles and no issues with 300k+ miles on the odo.

Here is an interesting read I just found on the topic. It uses a K&N drop in versus OEM on a diesel.

Effect Of OEM Style And Aftermarket Performance Air Filters On
Vehicle Parameters.

bob213 wrote:
Not a good thing for a diesel. Test show that the stock filter for the duramax is the best one out there. In the test K&N let in far more dirt which will foul the MAF sensor. I had one in my gasser Tundra and saw no real improvement. I went back to the stock filter.

What fouls the MAF sensor is over oiling the filter media, not the filter itself.

I have a full cold air intake on my Powerstroke and my mileage increased, so did the seat of the pants power.

I think K&N filters are overpriced, at least the air filters.

I did forget to mention $350 is for the Cool air Intake system not just filter. Wish I could have seen this before now since it kinda derailed a little