Several items to bring attention to.
5HP can't be felt by seat of the pants. 10 hp gain is just perceivable, then that gain is not every where in the rpm band except at the higher end.
The K/N filter is made with a more course structure and needs the oil to catch the dirt.
You may indeed see more airflow thru this filter as long as the motor needs it.
Often a new/clean filter does a worse job at filtering until some dirt builds up on its surface creating a smaller flow thru areas that traps even finer dirt particles, in micron size.
Let it get to dirty, the oil dries out, gets pulled out of the filter, then more dirt passes.
I have water filter I must use to keep water clean. If it is left to long, the water forces a path by the blocked filter and dirt flows again.
It all depends on how often and how well you keep a check on and maintain this type of filter.
Hint, auto trans fluid works fine as a filtering oil on a short term basis.
Used the trick for years on foam filters.

 

Yep, to all of it.

 

I've yet to have a problem with a K&N filter on any vehicle I've used it in. And I've yet to get rid of any of my vehicles without putting at least 300K+ miles on 'em. But who knows, maybe this F150 will be the exception. Hope not though, as I DO like it.

I do pretty much agree with what Bluegrass says. But to expand on one point....."It all depends on how often and how well you keep a check on and maintain YOUR VEHICLE.

Unless you plan on keeping your vehicle for more than a couple hundred K miles, replacing with an OEM type filter at the normal intervals would be just as cost effective for the average owner.

I just get attached to things and like to keep 'em.

 

I put a K&N Air Filter (filter alone, not the kit) in my rig. I felt my '04, 5.4 ran a little peppier. However, when I wash my rig I also feel that peppiness.

There is a good thread I started on this topic:

https://www.f150online.com/forums/sh...BN+Intake+Kits

My take from the above thread was that the K&N functioned at a level according to the feelings of the new K&N owner. Some felt added performance, others did not.

 

How much does a high quality paper filter cost? I was thinking about $15 and would need to be changed about avery 15,000 or 20,000 miles? pretty dusty around here. I clean my K&N every 15,000 miles, paid $45 for it, so I figure at 60,000 or so I'v saved enough to cover it.

 

I paid 13 bucks for a Napa Gold (Wix) including tax last month. Figuring you change it about every 25k if you live where there are paved roads and drive on said paved roads, you need to drive over 100k to get a K&N to pay for itself. Don't forget the cost of the cleaning and oiling kit over and above the price of the filter when you do your math.

 

i havent yet begun to work on F150's (just got mine like 7 hours ago) but i can tell you that i built a CAI for my ranger from parts at home depot. cost me about 20$ in PVC and fittings and another 40 for a filter from autozone.

its pure hawtness what you can do with some pvc glue, a few rubber fittings and about 2' of black PVC.