I thought I would start this thread due to the recent issues some owners have expressed concerning aftermarket air intake systems(specifically K&N)
First, some points recently taken from a Ford Diesel Tech

6.0L Power Stroke Diesel Super Duty and Excursion Air Filtration Q&A

Q: Don't all filters stop the same amount of contaminants from getting into the engine and turbo?
A: Absolutely not! The 6.0L OE filter, produced by Donaldson Company, Inc., stops 99.99% of contaminants the size of one micron or larger. Some aftermarket filters trap only 95%. What does this mean to an owner? Driven in the same conditions, a 99.00% filter would pass 10 grams of contaminant through to the engine that would be trapped by the 6.0L OE filter, and a 95% filter would pass 50 grams! This could mean an early end to your engine or turbo.


Q: Won't aftermarket airbox modifications, which use a lower priced filter, save me money?
A: Don't be fooled by aftermarket tactics of comparing the cost of one filter because you also need to know how often you'll need to change filters. The 6.0L OE filter holds more than three pounds of dust, dirt and soot. The aftermarket kits tested by Donaldson Company, Inc. held about half this amount. And don't forget, if these replacement filters are less than 99.99% efficient, they pass some contaminant through to the engine that the OE filter would have stopped!


Q: How frequently do the 6.0L OE air filters need to be changed?
A: Everybody's driving habits and environments are different. Owners/Dealers should check the air filterrestriction gauge (located on the upper housing of the air cleaner assembly) at each oil change interval todetermine when the filter needs to be changed. Some vehicles also have a dash light that will illuminatewhen the filter needs to be changed. No replacement is necessary until the filter minder (or dash light) gives indication.


Q: My filter minder doesn't seem to move, so shouldn't I check or change the filter to be safe?
A: The filter minder is a gauge that starts registering only after the filter reaches a certain point of being filled. This is why owners do not see it consistently move (like a gas gauge). Rest assured, the filter minder works and there is no reason to check on the filter by removing the airbox cover, thereby increasing the risk of contaminants entering the air intake system. Remember, the 6.0L OE air filter holds more than three pounds of contaminant – so it will take some time to fill!


Q: I want maximum airflow through the system to provide more power. Don't some aftermarket filters provide more airflow than the 6.0L OE air filter?
A: Airflow should not be the determining factor in buying a filter. Think about it: would you ever operate without a filter in place even though you'd get maximum air flow? High airflow generally means the filter is less efficient at stopping contaminants, too. Owners should instead look for the combination of three factors: airflow, how small of contaminant the filter will stop, and how much contaminant the filter will hold. The 6.0L OE filtration system provides a great combination and it comes standard on all Super Duty and Excursion trucks!


Q: If the 6.0L OE filtration system is so effective and efficient, why would anybody pay to modify it?
A: Excellent question. It makes no sense to pay hard earned money to go backwards in technology – especially considering that such modifications may even put future warranty repairs in jeopardy. You invested in your 6.0L Power Stroke Diesel truck to provide years of dependable service. Ford engineered it with a great filtration. So just why would anyone pay to modify it?
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Here is K&N's position for those of you that have this setup.




K&N Million Mile Limited Warranty® and Consumer Protection Pledge
K&N warrants its OE Replacement Air Filters for one million miles. When used properly and found to be defective, return your filter and the receipt from purchase and K&N will replace it free of charge. K&N’s Consumer Protection Plan goes one step further than its Million Mile Warranty. The performance aftermarket has, at times, been plagued by car manufacturers and automotive dealers that may attempt to discourage you from customizing your vehicle. They prefer you buy OE parts and not modify your car or truck and have even been known to void their own manufacturer’s warranty due to vehicle modification. That sounds un-American to us, which is why K&N and the Magnuson-Moss Warranty Act protect consumers from such denied warranty claims. When you buy an O/E replacement K&N High-Flow Air Filter or High-Flow Air Intake System you can be confident your vehicle's warranty will remain in effect. If you experience a difficult dealership, K&N will resolve the issue so you won't have to. The following summarizes the K&N Consumer Protection Pledge:

We want to make sure that when you buy a K&N Lifetime Air Filter or Air Intake System, you can be confident your vehicle's warranty will not be impacted. We also want you to feel confident that even if you experience a difficult dealership, we will step-in and resolve the issue, so you won't have to. Therefore, we make the following Pledge:

K&N pledges to our customers that they will not be taken advantage of and charged for a repair due to a dealership warranty denial blamed on the presence of a K&N product.

Steven Rogers, CEO


Is this for real? Anybody here have any warranty issues?

 

Might need the original reciept and the box... Lol

 

Actually, in that thread the owner said that he didn't have a K&N on the truck and based on service records of the truck at a Ford Dealership, the previous owner was never cited as having an a/m intake on the truck either. However, a Ford engineer claimed that the owner's problem was due to a K&N filter being on the truck.

I find it strange that they claimed a K&N filter was on there instead of just saying an a/m intake was on there and that's why it's having issues. The OP never cited stickers being on the truck or anything overtly K&N, but that's what Ford cited as the cause of the problem by specifically claiming K&N.

Now this is all based on what I've gleaned from that thread, I may or may not know the whole story, it's just what's in that thread.

Now I did notice several "ways out" that K&N has even in their pledge, just based on how that pledge was worded, so it isn't as good as one might think it is at face value. Plus if people would just do a little more research on a/m intakes in general for the 6.0 specifically, the products themselves aren't good for the stock and/or just tuned 6.0 population.