I recently bought a 99 F150, 4.6, 3.55 and after looking at all these posts, i am now considering dumping the stock filter and going with a K&N. I'm wandering if it will actual improve my mileage. Could you guys please give me your experiences with the K&N. Any help would be greatly appreciated.

 

i bought the k&N filter because of the cost of buying a new filter every 10,000 miles or so was to much cost, where I can buy the K&N filter once and clean it over and over again. I do see a increase in the power curve when I pass cars doing 60 to 80 miles and hour but that is all the power increase I see. No increase in gas milage.

 

I wouldn't do it to improve mileage; it didn't.


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2000 F-150 XL, RC, LB, 5.4L, 4R70W, 3.55LS,
Class III tow, Payload #3, & Convenience pkgs.,
4-wheel disc/ABS, Chestnut/Parchment 40/60,
Ford bedliner w/Paintsaver & gas/wheel/spare locks,
K&N F.I.P.K. w/Outwears pre-filter, Superchip,
Dynomax ultra-flow welded 3" cat-back w/ 3" Y-pipe,
Hellwig front & rear anti-sway bars, Rancho RS 9000s,
Mobil 1, K&N oil filter.

 

I have not noticed any fuel gains with the K&N filter.

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2000 F-150 XLT, 4x2, 5.4L Supercab, Superchip, Styleside, Black with silver two-tone, 3.55 rear, class III towing package with super engine cooling/auxiliary transmission cooling HD package, Heavy duty shocks, 4 wheel disk ABS, overhead console, sliding rear window, keyless entry, dark graphite interior, in dash CD, factory leather wrapped steering wheel, FORD bedliner, FORD black tubular cab steps, K&N air filter, mar-hyde rubberized undercoating, Modine climate filtration system, Bugflector II, Mobil 1 oil, build 7/2000

 

no mileage difference here. 13.4mpg almost exactly everytime i fill up. the truck doesnt kick down outta overdrive as much though so i know it gave it a little boost in performance.

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1998 xlt off road 5.4lsupercab auto pacific green clearcoat power drivers seat, keyless remote with factory alarm, tow package

2001 yamaha 660r raptor 4 wheeler

 

Same for me, no mpg change. Love that sound though.

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2001 F150 4X4 Lariat SC w/ Short Box
Black w/ Med. Parchment Interior
5.4L
3.55 LS
ORP
Power Moonroof
Heated Captain's Chairs
Tow Package w/ 1.02" radiator
Cab Steps
Bed-X-Tender
Weatherguard Box # 127-5
K&N ( homemade kit! )
Superchip
Delivered 3-7
Toy towed: 2000 Ranger R-93 w/ 200 Merc

 

The K&N filter definately lets a lot more air through it than a stock paper one. I went to a motortports store that had a neat little setup that had enclosed fans which would blow through a filter and then lift up one of those little plastic ***** in a clear plastic tube, to meausre air flow. You could put a stock paper filter in the hole for the fans to blow through, then an identically sized K& N filter. With the K&N, there was easily enough airflow through it to keep the ball in the top of the tube. With the stock filter in place, the ball would not even lift up from the bottom. So, there is proof that they do work as advertised. As for actual performance gains, that can be subjective. However, they DO let the engine breathe a bit easier.

 

The power gains are subtle. Last weekend I took the K&N out for a cleaning. I installed the stock paper filter in the interm. The truck lost all it's pep. This is about the only way to tell that the K&N works. BTW, my filter has 30K miles on it from use in my 97 F150 then I moved it to my 99 Superduty and have put 60k miles on it there. I've cleanded it prolly 4 times. The only problem I have had with it is the foam seal on the filter side came loose. Fixed that with some sealant I had laying around. Each time I clean the filter I also inspect the filter ducting. So far, no dirt inside.

 

Did not notice any change in power or fuel consumption. I did however get a real neat little K&N sticker, which should keep the clowns at quickie lube out of the canister.

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2001 Lariat Screw. Gen.3,
5.4, 4x4, All white w/ gray interior. 4r70w tranny, no problems yet,
wrong radiator, 3.55 gears