BlueZips Report post Posted January 22, 2014 Just purchased a K&N replacement air filter to drop into the stock air box. The stock air filter looks like it was made out of folded up yellow pages lol. It didnt look dirty at all, there were some small flying insects caught in the pleats tho. I thought i would try out this filter because it wasnt too expensive, and maybe try to get better mileage, hp, who knows......I will post some updates on how the filter performs. I dropped the filter in last night and drove to work this morning. Forgot to look at what the trip mpg was. Quote Share this post Link to post Share on other sites
acdii Report post Posted January 22, 2014 oh no, not again. Petunias. I would rather not get started on K&N and how poor they do in protecting an engine, but It's yours, do what you want with it. Quote Share this post Link to post Share on other sites
tr7driver Report post Posted January 23, 2014 Do you have oil this filter or is it a throw away? Quote Share this post Link to post Share on other sites
ptjones Report post Posted January 23, 2014 Do you have oil this filter or is it a throw away?It comes preoiled and will need to be cleaned periodically, every 50K miles and should last the life of the car. I have one in my CMAX, but I think MPG improvement is less than 1 mpg. IMO :) Paul Quote Share this post Link to post Share on other sites
billford Report post Posted January 23, 2014 Before you do any modifications, including the air filter, make sure it does not affect the factory warranty terms. If there is engine damage later, they may deny warranty, even if it is not a result of the aftermarket air filter. Quote Share this post Link to post Share on other sites
acdii Report post Posted January 23, 2014 The oil has been known to cause MAF issues. If any of it gets on the sensor it can destroy it, you dont even have to see any oil, it doesn't take much at all. Just remember this, lower restriction means larger openings in the filter, larger openings means smaller dirt particles can get through and cause engine damage. The thing about these particular filters is they need to get dirty before they become effective at filtering the dirt out. until they do, they let very fine dust get through and sucked into the engine. On Hybrids, until I see certified documented proof an aftermarket device, no matter what it is, actually helps to improve fuel economy, I won't put it anywhere near my car. I certainly wouldn't put something like this on for under a 1 MPG gain and take the risk of ingesting dust into the engine. Years ago I fell into the K&N theory and put one on a 97 Explorer V8, other than being louder on the intake, I saw no improvements to warrant the cost of the filter, and after 6 months during a routine check I found dust on the inside of the intake tube. Needless to say it went in the trash. I have used AFE filters though and wouldn't hesitate to use them again. I had one on my 99 F350 and after 60K miles the intake was spotless, much better than the stock box setup ever was. 1 decypher44 reacted to this Quote Share this post Link to post Share on other sites
GrySql Report post Posted January 23, 2014 I have an AFE on my Mustang and cleaned it a short while ago. Looked at the MAF and connections while I was at it, squeaky clean. 1 acdii reacted to this Quote Share this post Link to post Share on other sites
acdii Report post Posted January 23, 2014 Thankfully I replaced the stock box with the AFE in time, the turbo was showing signs of dusting. The blades were showing some rounding of the leading edges. Quote Share this post Link to post Share on other sites
ptjones Report post Posted January 23, 2014 The oil has been known to cause MAF issues. If any of it gets on the sensor it can destroy it, you dont even have to see any oil, it doesn't take much at all. Just remember this, lower restriction means larger openings in the filter, larger openings means smaller dirt particles can get through and cause engine damage. The thing about these particular filters is they need to get dirty before they become effective at filtering the dirt out. until they do, they let very fine dust get through and sucked into the engine. On Hybrids, until I see certified documented proof an aftermarket device, no matter what it is, actually helps to improve fuel economy, I won't put it anywhere near my car. I certainly wouldn't put something like this on for under a 1 MPG gain and take the risk of ingesting dust into the engine. Years ago I fell into the K&N theory and put one on a 97 Explorer V8, other than being louder on the intake, I saw no improvements to warrant the cost of the filter, and after 6 months during a routine check I found dust on the inside of the intake tube. Needless to say it went in the trash. I have used AFE filters though and wouldn't hesitate to use them again. I had one on my 99 F350 and after 60K miles the intake was spotless, much better than the stock box setup ever was. Lower restriction doesn't necessarily mean bigger holes, in K&N (I have one in my CMAX) air filter has more surface area, you can see the difference with filters side by side. The larger the surface area the less restriction.There are several members in CMAX forum that have K&N air filters so we will see how it goes. FFH it is easy to change air filters unlike CMAX which is a pain. MPG improvement is less than 1 mpg IMO so far :) Paul. Quote Share this post Link to post Share on other sites
acdii Report post Posted January 24, 2014 I dont know about your filter, but I saw light through mine, clearly, through holes. There are no gains to get by using one on the Hybrid, but for my Flex, a cold air kit with a good dry filter is worth doing, but only a dry filter like AEM of AFE, dusted turbos are quite expensive to replace. When I saw the fine dust inside the t=intake past the filter, that was enough to convince me not to use the k&n again. Better safe than sorry. Quote Share this post Link to post Share on other sites
Iwejun Report post Posted February 12, 2015 I've run K&N filter cold air intake and a Banks cold air intake on both my 7.3 turbo diesel and 6.0 turbo diesel 350's and never saw even a light sheen of dust entering into the turbo inlet. Some people will call snake oil without even doing due diligence. 1 ptjones reacted to this Quote Share this post Link to post Share on other sites
Griswald Report post Posted February 12, 2015 I've used K&N filters on everything I have owned since 1985. I've used Mobil 1 in everything I have owned since 1985. You'd think both of those companies would be out of business by now with all the internet warnings that get posted. Guess what...both companies are still in business and doing well. Must mean something. 1 ptjones reacted to this Quote Share this post Link to post Share on other sites
billford Report post Posted February 13, 2015 People seem to love them or hate them. My opinion is, if the manufacturer could squeeze even a minor amount of extra power or fuel economy using the K&N without compromising the engine, I think they would have used them. Maybe there's a reason why they don't.. 2 acdii and Texasota reacted to this Quote Share this post Link to post Share on other sites
GrySql Report post Posted February 13, 2015 (edited) Believe it or not, back in the late 1960's/early 1970's, when we were racing VW Baja Bugs in Baja California we'd wrap a piece of thin foam soaked in transmission fluid around our paper carburetor filters.That effectively trapped most of that famous Baja silty dust and worked pretty good, until the oily foam got too sludged up with silt. Easy to clean too, remove the foam, pour some gasoline on it, wring it out, let it dry for a few minutes in the 100F+ Baja air, spray some trans oil on it and we were off again. The guys who started K&N were there with their motorcycle filters, they used oil soaked cotton instead. Camped on the beach in Baja, 1974: Edited February 13, 2015 by GrySql 1 hybridbear reacted to this Quote Share this post Link to post Share on other sites
Griswald Report post Posted February 13, 2015 People seem to love them or hate them. My opinion is, if the manufacturer could squeeze even a minor amount of extra power or fuel economy using the K&N without compromising the engine, I think they would have used them. Maybe there's a reason why they don't.. Its a cost vs. benefit issue. Paper is cheap, cotton is not. Quote Share this post Link to post Share on other sites
BNOBLE Report post Posted January 21, 2018 Any updates from K&N users?K&N part number used?Anyone try cold air intake system, if available?Note for nay Sayers: I have put over 250,000 miles on Ford Ranger, Dodge Dakota and currently Chevy Colorado (353k)all with K&N drop in air filters. No problem. Quote Share this post Link to post Share on other sites
ptjones Report post Posted January 23, 2018 I currently have 140K miles on my K&N air filter #33-5001 which is the same for FFH. I have 178K miles total and 13k ICE miles( about 26K odometer miles) on my last oil change and my BlackStone oil analyses was the best so far. :yahoo: I definitely think it helped acceleration, but not MPG much. BTW I haven't changed it because it is a pain to change on the CMAX. ;( Paul Quote Share this post Link to post Share on other sites