[mndmax]

New D/A owner here. I am wondering what the pro's and con's are to each of these intake systems. I see lots of positive comments about the AFE. Any reason to stay away from the K&N?

 

[Georgecls]

From a lube engineer's perspective and/or if you expect to keep your Duramax for a long, long time, I would highly recommend an oiled foam vs. an oiled gauze type. A high quality oiled from like that from Unifilter or Amsoil does an excellent job of flowing air AND filtering dirt. Oiled gauze flows air very well and keeps out bricks and birds pretty effectively, but that is about it... Visualize a dirt particle traveling at over 100 miles an hour approaching an oiled gauze screen; there is no tackifier on this earth that will reach out and grab that particle; it is going into the turbo/intake.. The oiled foam forms a labrinth enabling the tackifier to capture the dirt particle. I review hundreds of oil analysis results a day and can spot an oiled gauze a mile away with its high double digit silicon and related elevated wear metals from high levels of abrasive in the oil. It takes but one teaspoon of dirt to totally destroy a large V-16 CAT engine; much less to affect our Duramax engines.. There are instances and installations where the oiled gauze/screen works fairly well but it is dependent on installation, area of country, type of driving, etc..
George Morrison, STLE CLS Edited by: Georgecls

 

[TheChevyHDMan]

Mndmax.......Dont worry, Ive been running a K&N and an AFE for 40,000 miles, And I go 7K before oil changes, and I have Oil Analysis done at every one....I dont know what oil shop George works at, My highest Silicon count was a 10, early in my engines life(could be from engine build) I usually score between a 5 and 9 every time....Actually I know alot of people that could disprove George on his Mile Away sight of a Guaze OA. I think the question here is interpritation of what George means. I think he comes off a touch strong on his opinion...Out of the 5 trucks I service running K&N's or AFE's (2dmax3 6.5) The highest spike(one time) was 15 on My 6.5, After both heads were replaced. For shizits and griggles I tested my fathers 6.5 that was running a stock airfilter....this isnt really proof, But it was worse than a K&N'ed truck.


Bill


Go buy the AFE stage II and dont worry, But for that self assurance feeling, Get an OA kit and prove it to yourself, Thats what I did.

 

[MOTO HEAD]

Does't K&N have about a zillion Baja victories to their name. I was under the understanding that an oiled foam will pass dirt when dirty and required more maintenance.

 

[Bill Gisse]

Hold a high quality new pleated paper filter up to a bright light and see how many holes you can see. Do the same with a new K&N filter and see the holes in it. I had a K&N filter in my 2003 GMC Duramax and after this little test I took it out. Also there was a oily film on the output side of the air chamber with a fair amout of dust stuck to it. I wonder how much free dust gets thru a K&N to eat at that high rpm turbo. My truck is only three months old so I'm back to the OEM filter until someone proves that K&N or any of the othe fancy filters catch all the dirt/grit that people think they do. I've used K&N for years and never questioned them. Like someone said elsewhere in the frum, good paper filters are not so expensive that one can't afford to replace them every 10-15K miles.I'd be more concerned with a good primary fuel filter than a fancy air filter. I'm putting one (Nicktane) on my truck now and maybe an supplemental oil filter next. In the mean time I'll stick with the Baldwin oil filter and change oil evry 5K miles for the first 15K milres. Already changed at 3K miles.Will change the Allison filter at 7.5 and 15k Miles. Synthetic tranny fluid is down the road somewhere but not until the first scheduled change is required.

 

[Georgecls]

The area of to K&N or not to K&N is about as controversial as with the discussion of oils, etc. As I indicated in my last line, there are indeed some (limited, tho, from my experience) installations were the K&N works fairly well. However, even in those cases one cannot just look at spectrographic oil analysis alone as spectro analyzes particles of 5 microns and smaller. Anything larger than 5 microns can go undetected. So, even tho a spectro oil analysis may return a 10 silicon rating, there may be much larger particles entering the turbo/engine which can cause conserable damage long term. I have no association with any filter manufacturer; I do review several hundred oil analysis results a day and see at least 10 to 15 oiled gauze equipped vehicles a week reflecting elevated wear rates. When changed back to paper or other depth type medium, wear rates reduce. And yes, I have seen many a Duramax experience significant increases in reported wear rates when switching to an oiled gauze and then reduced back when reverting back to paper or depth type. Moreover, my only intent is to make people aware that there may be a price to pay for the K&N woosh, depending on the individuals goals are for his/her Duramax. Regarding the Baja. Yes, if one is only concerned about their engine lasting the length of the Baja, indeed, it keeps bricks and birds out very well. I have seen one too many sanded turbo vane/engine.. I am sharing my experiences only so one can make an educated choice.
George Morrison, STLE CLSEdited by: Georgecls

 

[Diesel Power]

I have to agree with george here. My real-world tests are crude at best, but here's what i did:


I used to have 2 quads, a honda 400ex (sold now) and a honda rancher (still have). i initially ran K&N filters on them until i noticed dust in my intake when i serviced the filters. i always serviced them after every run, cleaned them, let them dry, and then re-oiled them. once i switched to a UNI foam filter, my intakes were clean. granted my dmax doesn't get run is as dustly of conditions, but logic would dictate that if dirt gets through in bad enviro, then some dust will get through in a cleaner enviro. also.


my 2 cents worth.


Nick

 

[hoot]

Does't K&N have about a zillion Baja victories to their name. I was under the understanding that an oiled foam will pass dirt when dirty and required more maintenance.

No they have about a zillion K&N decals to their name. You can be sure those rigs have specially modified air filter systems. Minimum being a foam cover...... possibly bought from Unifilter

I believe an oiled foam filter stops passing air when dirty. That is what it is supposed to do.

Another problem with K&N gauze style filters is the damage to the fiber structure that occurs every time you wash it. They loose efficiency after each cleaning.

My Amsoil 2 Stage is a thick. When it was dirty, the entry side was caked (I left it in too long). The exit side looked brand new. Looks alone does not mean it's working, I agree. I just like the thicker media as apposed to the paper thin gauze.

I guess oil anal is the key.Edited by: hoot

 

[LARSONEM]

Interesting discussion here. My sitter's husband has a 2002 K3500 D/A and I have a 2003 2500HD D/A. Both trucks are stock in terms of no high performance parts like programmer boxes or exhaust mods. He has switched to a K&N. What Jim believes is that everything that is on his truck automatically works for everyone else. I don't believe that. Personally I would prefer to pitch the paper element and replace it with a new paper element when it's dirty. Jim would rather wash and reoil the K&N and believes it provides superior air flow resulting in improved fuel economy. Jim's truck is never driven off road and is used 100% for trailer towing. I run mine off road sometimes and use it as a daily driver, plus towing. I think the paper element does a fine job. His contention isn't that the K&N provides superior filtering capabilities, but that it provides superior air flow.


If you want to talk about superior filtering capabilities, then I suggest you look at my John Deere garden tractor. It has a paper filter and a foam ring that goes over it which I clean and reoil every 15 hours. Talk about something that traps a lot of crud!


So do what makes you feel good. I can't believe that the OEM filter from GM does a bad job filtering or else GM would improve on it.

 

[bybycop]

I have to agree with george here. My real-world tests are crude at best, but here's what i did:


I used to have 2 quads, a honda 400ex (sold now) and a honda rancher (still have). i initially ran K&N filters on them until i noticed dust in my intake when i serviced the filters. i always serviced them after every run, cleaned them, let them dry, and then re-oiled them. once i switched to a UNI foam filter, my intakes were clean. granted my dmax doesn't get run is as dustly of conditions, but logic would dictate that if dirt gets through in bad enviro, then some dust will get through in a cleaner enviro. also.


my 2 cents worth.


Nick

I couldnt agree with Nick more! K&N is good but Since I put Uni foam filters There is no more dirt getting in. I live in a very dusty climate and have to worry about it. The shops are what turned me to foam filters for all of my toys. Ive ran a K& N in three different trucks and have been happy but Im going to get a different type for my Duramax. Im doing my hopework as we speak.


Mike

 

[Camstyn]

It's no cooincidence that every high performance dirtbike uses foam filters. I wouldn't even think of using a paper element filter on my bike.. I'll use it on my truck though, I don't chase other trucks through the desert, woods or MX track with my truck. The paper filter gets the job done for the truck's purpose. Your mileage my vary.