This site has alot of info on the K&N filter used on duramax diesel truck.

The results are not very good.

I was going to run a K&N but now I am not so sure.

Please check it out and post your thoughts.

http://www.duramax-diesel.com/spicer/index.htm

Mitsuatb

 

It isn't entirely surprising that the least restrictive filter (K&N) also passed the most dirt.

It isn't entirely surprising either that the test demonstrated that K&N's marketing hype is sorely overblown. I've used K&N filters for years, but calling it a "filtercharger" is offputting.

 

It's a basic tradeoff; performance vs. longevity. I had a K&N cone filter on my Nissan for 160k miles without serious issues. The compressor wheel does show signs of wear from debris, some pitting and a bit like it's sand blasted, after about 80k miles on it.

So if you plan on keeping the car for 150k miles, maybe stick with the stock filter. If you live in a dusty area, say the desert, you might want to stay with the stock filter. If you're willing to give up some longevity for some performance, get one of the oiled filters.

 

The K & N plugging up so fast was a surprise to me.

I thought a depth filter should have plugged slower than a paper one.

Almost like the K&N had less filter area.

The wire mesh may not be helping. Paper doesn't have a support structure. Same area would have more flow surface.

Lots worse than I expected.

I have run a K&N on a LT1 Camaro for 106,000 miles. Still doesn't use oil, so that is a good result. Makes me wonder if it was a good idea or not.

Food for thought.

Mitsuatb

 

Ttt

 

I've used the same K&N air filter on my talon for well over 200k miles. Probably 250k. It has 278k miles and has not been rebuilt. Turbos have lasted me 100k+ miles until the oil seals start to weep, and I have not noticed any abnormal wear or issues I could say were air filter related. I'm sure you could break out the microscopes and find results that showed the more dirt was passed, and there was extra wear related to it, but for a non-desert, road driven vehicle, the lesser filtration does not seem to be an issue from my experience.

 

I am still running stock air filters because despite K&N "being ok" all the way to "awesome" according to countless people I have always:

1- found them too oily, and coating my MAF. New or oiled after a cleaning. It's even trickier to get just the right amount of oil on them.

2. found them horribly inconsistent and porous out of the box, which just gets worse with time and cleanings-re-oilings. Try taking a brand new one and a used one, and hold them up to the light. The gauze sucks.

3. even with a brand new one, on an NA engine, i not only found oil residue deposits on the MAF and intake tube, but SEDIMENT stuck in the residue.

4. I live in a dusty area.

so based on that, the very minimal and usually pretty negligible "performance gains", stacked against the cost of OEM replacements and hassle of cleaning and re-oiling the ever-deteriorating K&Ns, I will stock with OEM filters, or some other Dry paper element.