Flow rate DOES remain constant, only pressure changes. When the filter elements are to resistive the bypass valve opens up to keep the pump from destroying the elements. Flow rate might drop slightly, but not significant. Only pressure changes. The oil pump is driven directly by the engine, and of a design that it always pumps a certain amount per RPM. No paper filter is going to battle that. In higher performance engines oil nozzles that require high pressure are installed in the crank to spray oil everywhere like a garden hose. They don't reduce flow rate, just increase pressure. Like trying to stop the flow from a garden hose with your thumb.

The only effect I can see from a K&N oil filter is reduced filtering performance.

If you were to compare flow rate between different oil filters it would be the same, because any filter that could actually reduce flow would have to be constructed of steel, not paper or cotton. A filter is made of paper in 60+PSI environments because that pressure is almost the same inside and outside of the filter. The pressure differential is there, but minor. Possibly not more than 5-10 PSI. If that filter because to restrict the flow of oil, the pressure will climb until the point where the oil filters bypass valve will open. During all of this, the flow rate remains the same because the additional pumping power comes from the engine, which I'm sure barely notices.

 

http://www.mazdastuff.com/product.cfm?ProductID=2168

the O/E filter and both o-rings for under $5.00 and a filter wrench that fits perfect

FYI, DJ

 

My Ford dealer who sold me the car does "first oil & filter change free".
Back in 2005, when I took mine in, they didn't have the filter in stock, and had to send someone cross-town to get one from a Mazda dealer.
My oil-change took 2.5 hours. But it was "free".

 

I when to 8 different car part places no one had one they could order one from $45 to 65 dollars ford was $65. Auto zone had the lifetime K&N for $53.00. Who would buy anything else regardless for air flow being able to clean saves you money on the first cleaning. Ill be honest not sure if having the K&N helps my car out but after changing my car to full syntetic oils and having the K&N air and oil filters I went from 31 to 34 MPG on my 06 FEH it all about the fuel economy.

 

watch project farm on YouTube on all the different air filters...I have seen other demos as well and will not be putting a K&N filter in anything I want to last!!

 

After the first year I used nothing but K&N in my 1988 Dodge Dakota truck. Had no trouble at all. Kept that truck for 21 years and 222,000 miles and sold it in perfect working order.

After the first year I used nothing but K&N in my 2005 Ford Escape Hybrid. Had no trouble at all. The FEH was in top running order for 234,500 miles until Rear-Ended in 2019 disabling the vehicle from behind. The engine was in excellent shape with oil changes every 15,000 miles. I did used oil analysis on the Escape. Test results were always in the green up to 21,000 miles on the oil.


Buying ONE air filter for the life of my Dodge saved me tons of time and money.

Buying ONE Engine air filter for the life of my FEH saved me tons of time and money.

Buying ONE HV battery air filter for the life of my FEH saved me tons of time and money. *

* I figured out and posted here years ago that a Yamaha motorcycle engine air filter was the same size as the HV battery air filter.

 

On some vehicles, the oil on the K&N engine air filter would contaminate the Mass Airflow Sensor and cause poor readings. This can lead to engine running issues like poor economy, and very rarely engine or catalytic converter damage. From reviews I have seen in the past,there replaceable engine oil filters are decent quality and ruggedly built but the value equation remain unfulfilled. I dislike cleaning oiled filters but the principle is a good one from an environmental perspective except for the oil part.. I use a washable MERV 8 furnace filter at home for that reason but it is a dry one.

 

I'm sure only a problem if you misused the Oiler air filters and over-oiled them.

They only need a trivial amount.
And then, only about every 100,000 miles unless you do a lot of miles on dusty dirt roads.

Huge environmental savings.
One cardboard package and one element for the life of the car.

 

there is the case that manufacturing changes over time - companies go over seas (china and etc).
you did not say what year that you put the k and n in the ford hybrid; perhaps the quality is not the same now.
i noticed that my 09 feh had a k and n air filter in it; dont know what year it was put in; i washed and reoiled - works good.
those that i talk to (and it is many) have seen k and n develop holes in them and they replaced them with another brand;
my feh is the first k and n that i have used (use a ractive on my 2008 kia sorento) and as said - there is no issues.
thanks for the tip about the hv filter - have to see if that applies to my 2009 (the ac filter for that is a little pricey)

 

I think I did say "after the first year" I switched to K&N. The air filters is mostly what I promote. One is good for the life of the car.
Some people mess with them too often.

I checked on mine every 20,000 miles. Just opened it up, shook off any loose debris such as dry leaves, dead insects, or spider webs and put it back in.

I only washed and reoiled (light on the oil don't soak it) every 100,000 miles. Which was only 2 times ever. The FEH was rear-ended at 235,000 miles.

That means I had the factory air filter in there for the first 10,000 ish, and the K&N in there for 225,000 ish miles. 2006 to 2019 on one air filter for the engine and one filter for the battery air compartment.