K&N air filter

[AnthologyCT]

OK fellas .......... here's one for ya

I'm at the dealer today buying some accessories ...... (Splash guards, touch pad for the back glass panel, and touch-up paint).

So I start up a conversation with one of the mechanics about gas mileage and trying to improve it. .................... First thing comes out of the guys mouth is ................ Don't waist your money on the K&N Filter.

........... and I'm like, "HUH!? .................. but everybody on JeepKJ.com swears by it!" He says that he's owned 2 Jeep Liberty Limited's ............ both 2003 pre-owned. In the first one, he had the regular Mopar air filter system. Then his wife totaled the vehicle. He said the vehicle was so good, he decided to buy another........... same year, just different color ...... (probably got a good discount from the dealer). But, this one came with the K&N air filter. He says he's noticed absolutely no difference between the 2.

So what gives guys? is the mechanic just tryin' to sell me air filters, or what? So many of you swear by it, that I'm inclined to believe you.

Also, he did say that he keeps his tire pressure a little high .......... but not to go over 36psi.

And, he uses synthetic.

Finally, he said, "If you want good gas mileage ........ buy the Diesel!"

Just some thoughts .......... what say y'all?

............................

by the way, I'm still looking for some used tow hooks & and a used subwoofer, and I'm not tryin' to pay nearly what's asked for on Ebay.

 

[MoladoGuy]

It takes more than just the air filter to raise your mpg (noticeably). I did not put a new Air intake system in, just the K&N filter. It's really sweet because I clean it at every oil change using the K&N cleaner.

For me, it has worked great in keeping nasties out of the intake, but it has also allowed it the breath better. However, I am not going to say that this alone has increased my gas mileage.

 

[GoldenRam]

I have a stock 04 Liberty Sport with the 3.7L ... for now. I've checked my MPG just about every fillup, usually 15 gallons. I have just about 30K on it now. I've used synthetic in it from the first oil change so I can't say if that changed my MPG. After 12K miles I put a K&N air filter in and I noticed an average of about 1-2MPG increase. It's not much but with gas prices these days it'll pay for itself in no time. With that aside I'd rather pay $50 once for a K&N than whatever there getting for a disposable filter every 12 or so thousand mile. I also use 89 octane which increased my MPG about the same. I drive maybe 70% city 30% highway. I started at 15MPG, now I get just over 18MPG.

 

[Tigrou]

I could not answer about 3.7 V6 but for the CRD with or without K&N there's no changes.

Each time nearly 500 miles with 90% of the gas tank

If i am right, it's nearly 27.6 MPG with the CRD #-o

 

[Brigrat]

I have used K&N's in a couple of vehicles, and have never noticed a real difference. On the flip side, like another poster said; you can clean them every oil change or two, and never have to buy a new filter, so from that standpoint they are good.

 

[Trodo]

Where I live I was having trouble finding standard air filters, so I went with the K&N panel filter just so I wouldn't have to worry about it anymore.
Recently I went over to a Rusty's KJ Airtube with a 5x8 K&N filter from Summit. Much improvement, but it's a total package, I've also done the muffler swap out and soon, the headers. Getting the engine to breathe in better and exhale better is the key to more mileage and power.

I also keep my tires at 36.5, don't know if that's good or bad for the tires, but I get decent mileage returns on the highway, and just above the norm on city. Plus at 36.5 the tires don't look underinflated when it's parked.

 

[JeepJeepster]

Ive found dust on the clean side of my K&N after offroading in ALOT of dust. Just be sure to change the oil often...

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[JJsKJ]

K&N flows better but lets way too much crap into the engine. It has been proven to allow more junk through the filter which over time is going to cause problems. I used to swear by them but further research has proven they are not worth it. BTW, I have an FIPK on my wifes KJ but as soon as I can get a better, dry filter for it the K&N version on there now is Gone!
I was also seeing dust in the intake tract for my stock system in my 03 w/ drop in K&N and in the FIPK on my wifes 04. The factory system flows more air than the engine can use, why bother messing w/ it.

 

[AnthologyCT]

Dust

K&N flows better but lets way too much crap into the engine. It has been proven to allow more junk through the filter which over time is going to cause problems. I used to swear by them but further research has proven they are not worth it. BTW, I have an FIPK on my wifes KJ but as soon as I can get a better, dry filter for it the K&N version on there now is Gone!
I was also seeing dust in the intake tract for my stock system in my 03 w/ drop in K&N and in the FIPK on my wifes 04. The factory system flows more air than the engine can use, why bother messing w/ it.

Hey man, can you post some of that data for us to see about the K&N filter's performance over time ............ about the dust.

 

[JJsKJ]

Here is some info. I am trying to find more but this will get it started. FWIW, The Amsoil filter tested is an oiled foam filter. It is not the same as the current line of Absolute Efficiency air filters that Amsoil has recently come out with which are Dry, not oiled. I will try to find more info to post.

http://www.bobistheoilguy.com/airfilter/airtest1.htm

There are lots of sites w/ similar info about the K&N filters but a lot of them I will say are biased towards the competition, some including Amsoil filters. I will try to not list those as I am personally looking for unbiased test results. I will however post up the Amsoil Vs. others testing done by Amsoil as you will see they report what they find regardless of whether or not it points out areas where their products are not as good as the competition.

Pics of my stock KJ intake sys that had a drop in K&N filter in it for about 10K miles. I have since switched to a Wix air filter w/ no more dust in intake tract.

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I do drive in very dusty conditions often and on other vehicles of mine that were only street driven w/ a K&N, I didn't notice this type of problem.
I also have Not seen any kind of performance change since switching from K&N back to WIX.

 

[JeepJeepster]

Oh gosh JJsKJ, thats not good at all. I just checked mine today and its clean as a whistle. I kinda want to change it out to a pureone, but my dad bought that for me and I would feel alittle bad to take it out. :-s

 

[NomadKJ]

Check out True Flow Foam air filter; http://www.trueflow.com/index.php

 

[JeepJeepster]

Wow, I was surprised at the dirt that got through the K&N filter, than I saw the paper filter. Im kinda confused by that test? All the filters seem to let alot of dirt through? Im really thinking of taking the K&N out, this really has me scared. :-k Im not sure what filter to use though, all the ones he tested seem to suck. :-s

 

[JJsKJ]

From other tests I have read, AC DELCO filters are some of the best for filtering but they do tend to bcome restrictive over time. REgardless of that, I doubt Delco makes a filter for the KJ. Wix air filters have always been good ones as are OEM Mopar ones. Or at least good enough overall. I have put in a request with Amsoil to make an Absolute Efficiency air filter for both stock air boxes and a cone style to replace the K&N on the FIPK. (Wix are available through my order site currently for stock KJ apps)
I wouldn't worry a lot about the K&N unless you do a lot of driving in a dusty area. People in more humid, damp areas probably won't see the dirt in the intake that I have seen here in the desert. However, if you are buying a K&N thinking it filters better than stock or flows so much better than stock that it will save $$ in fuel mileage, don't bother, Save your money. Obviously my HO and $.02. Take it FWIW.

 

[jwheeles]

K & N air filters

I put the drop in K & N in my '05. I really couldn't tell any difference in mileage or power. It may have helped but it would have been very minimal.

I replaced the drop in K & N with the new K & N cold air FIPK intake. (They finally released one CARB approved for the "05). If anything it hurt mileage. Power may be slightly better. It's hard to tell for sure. The big difference with the cold air with the cone filter is the sound from under the hood.

I just got back from a 300 mile trip with most of it on the interstate. My mileage was just over 20 MPG. Check specs for mods on my KJ.

 

[JeepJeepster]

Thats great that you got over 20mpg with the 245/75/16 tires! They must not cut down on mpg that much. :-k

 

[jwheeles]

Mileage

I got between 22 and 23 a year ago when I was driving to Tuscaloosa to watch the Crimson Tide play on Saturdays. It was also pretty new at the time. I've got about 23500 miles on it now. The mileage yesterday worked out to 20.2.

The stuff I've done has dropped it by about 2 MPG's. I'm attributing most of the drop in mileage to the tires and lift.

I drive with the cruise set right on 70 MPH. This was roughly 150 miles each way. Considering the tire size I'm guessing this is somewhere in the 72-73 MPH range.