Looking to buy the K&N kit for my '02 Yukon XL. Has anyone purchased this kit for your trucks? Looks like it will be in the neighborhood of $280. Will never have to buy filters again. Any comments would be great.

voids warrantee on our diesels. I prefer the afe filter to k+n, and cummins is ok with them. http://www.advancedflowengineering.com not the right url sorry

Keep in mind that a turbo charged diesel pulls twice the air as a similarly equipped gas engine. K&N like alot of others use the same air filter. Just using a K&N replacement air filter on a 6.6 Duramax is the kiss of death. The stock OEM filter element is reinforced with expanded steel on one side and beads of hot glue on the open side. The K&N gas engine "Carry Over" will colapse like an accordian when it gets partially restricted allowing all dirt & debris to enter the engine. Who was it that said "Pay Me Now or Pay Me Later" !!!

the k&n kit is the cold air kit you are referring to right? what bothers me about those kit`s is the perception that snow dust might be an issue . i have never had an open element like that so i cant say for sure...i did have a regular k&n in my fullsize bronco and i really liked it . M

Originally posted by Thumbdoctor@Sep 10 2005, 04:37 PM
Keep in mind that a turbo charged diesel pulls twice the air as a similarly equipped gas engine. K&N like alot of others use the same air filter. Just using a K&N replacement air filter on a 6.6 Duramax is the kiss of death. The stock OEM filter element is reinforced with expanded steel on one side and beads of hot glue on the open side. The K&N gas engine "Carry Over" will colapse like an accordian when it gets partially restricted allowing all dirt & debris to enter the engine. Who was it that said "Pay Me Now or Pay Me Later" !!!
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So are these replacement filters still so poor? The guy at the parts counter was really raving about this filter. I told him I didn't want to put $45 in to a filter if I may go with the whole kit in the near future. Are any other brands better?

I'm not going to recommend any brand on this cold air system question (cause I don't know all thats available). Here are some facts I do know.
1) GM has Dyno tested a lot of these products and found little performance increase (read imperceptible from the drivers seat) or reduced performance due to emission system roll back.
2) When air filter maintenance is left up to the average consumer it is generally overlooked (after-market air filters need to be washed and oiled).
3) Some of these systems (not all) do offer improvement in volumetric efficiency when combined with other engine equipment such as Free flowing exhaust systems, Belt / exhaust driven super chargers, high lift / duration camshafts.
4) Factory air cleaner units operate best within the Load / RPM parameters the vehicle was designed to operate. More RPM = more fuel consumption.
5) Some vehicle manufacturers / dealers are looking for a "scapegoat" to blame any warrantable driveability problem or catastrophic drivetrain failure on after-market add ons. It is the burden of said manufacturer / dealer to prove the cause of the failure.
6) A lot of add ons generally reduce the fuel mileage due to the placebo (sounds cool) effect where the operator is actually the cause of the reduced fuel economy.

In closing, I believe some of these products do deliver what they allege as long as you read & understand the fine print and disclaimers. The real question is:
Are you getting real value for your investment dollar ?

A wiser man than me once said " Good, Fast, Cheap, Take any one away and chances are, you don't get the other two".

End of Sunday sermon

fwiw i picked up 1 mpg constant on every tank after the install .and it did sound cool when i put my foot in it . the filter had 150000 miles on it when i got rid of it and looked like the day i put it in .i cleaned it once a year on easter weekend so i could remember.your experience may differ from mine ,i`m just throwing in my .02 cent`s

My brother has one on his Z-24 Cavalier and has also put a exhaust on from the header back. He has said numerous times that he has picked up gas mileage. Probably about 2mpg, as far as horsepower, nothing that he can tell just by driving it. He put the intake and the exhaust on at the same time, so cant say if one or the other increased the gas mileage.

I agree with you doc, however the biggest restriction in my truck was the intake system gaining over 280cfm @26in of air through the newer one. they design them to be quiet and cheap(really number 1) as well which is a downer when it comes to air movement. I would by the cleanable filter just for that, not looking for any other gains. now diesel I will promise you differant results. noting in our testing we seen a drop in egts of over 300 degrees with the change, I can assure you it was from more air entering the system. drop allowed us the fuel to push 50rwhp more at the safe temps. http://www.afefilters.com

i made a CAI for my car and although the gains are few they are noticeable, and you hear an awesome sucking sound under WOT. :)

Put the system on my 6.0 chevy. Helped my mileage a little, very little, but the way gas is these days any little bit helps. Performance gains also minimal.

k&n will let enough sand through to polish up a few parts.

Originally posted by paul yarek@Sep 14 2005, 06:30 PM
k&n will let enough sand through to polish up a few parts.
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Yup.

I was a hardcore K&N user for many years, mainly in my toys but eventually in my daily drivers. Untill one day I found dirt in the air tube thats between the air box and the throttle body. The K&N was tight and no signs of damage so I investigated further.

One of the facts about K&N and now thier competitors is that they flow lots of air...which in some cases improves performance and milage. These cotton fiber filter companies say its the oiled cotton that allows them to breath better than the typical paper element.

This is true. Why? Because the cotton fibers have huge holes in them as compared to paper elements. Net result....dirt gets past the filter and right into the engine.

Another issue that dealers and the manufactures are dealing with is what they filter oil does to the sencitive sensors and emmisions crap. Many K&N and the like users dont take the appropriate time to allow the excess oil to drain from the filter, and over oiling them is extreamly easy to do. Well alot of that oil makes its way into the airflow. Todays newer EFI and TB engines dont like sticky goo getting to the MAP, MAF, and all the other sensitive metering devices.

Im sure that in the very near future you will see that the auto manufactures will all start voiding any warrentee's that can be related to the oiled cotton fiber filters.

My CTD is due for an air system upgrade this fall. I was thinking about the AFE or BHAF, nto sure yet. Jim I would stay clear of the KN system all together.

My 3 cents

Perm

Thanks guys for all the info...I knew you would have some experience with these things. Looks like I'll be staying with the $10 paper filters for a while.

Originally posted by TR800@Sep 15 2005, 07:41 AM
Yup.

I was a hardcore K&N user for many years, mainly in my toys but eventually in my daily drivers. Untill one day I found dirt in the air tube thats between the air box and the throttle body. The K&N was tight and no signs of damage so I investigated further.
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i've also seen chips out of turbo fins from dirt allowed through a k&n.

one has to remember the reality of the cotton fiber it will shrink eventually. oiled foam is the best method of higher air flow that is not contaminated. the afe pro gaurd 7 is the best in my opinion, and us hard core diesel guys sample our oil so we know whats in it.

Using an "oiled" filter on any engine with a mass air flow sensor is a no no. The oil residue will eventually make its way onto the sensor element and contaminate it. We see several emissions test failures, loss of performance and mileage complaints from use of these types of filters. Price out a new MAF sensor before desciding to install one. You will need a new sensor eventually.