I have a 1999 V10 F-350 with a K&N air filter, but from what i've read on these forums, it might not be the best choice for my current situation, which is that i live at an elevation of 7,000 feet, drive on and off-road. i have enough power with the V10, so i don't care about increased HP, but would like to use the filter that would give me the best MPG at this elevation. suggestions?

PS- i do NOT wish to start a K&N debate, just looking for recommendations based on my particular situation.

PPS- i have no mods and don't want to make any, though i respect that some people like them...

thanks!

 

Motorcraft FA1632

 

I am guessing that part of your concern is the off road use? If it is pure filtration you are concerned with, maybe a pre-filter sleeve would ease your concern as to fine dust partical entering the system. A K&N is nice from the stand point that you will never have to purchase another air filter. You will need the recharge kit to keep it clean and reoiled, but one kit last a long, long time. Need to be careful not to over oil the filter, which could trigger a problem.
In the past K&N was the way to go, however manufactures have come a long way in improving the quality of OEM filters and fine tuning the air intake. On my V-10 I will likely stick with the factory set up. On my 450 PSD, I changed to aftermarket due to the fit problems with the factory air box seal. It allowed dirt to enter the intake and dusted the turbo, caused a non warranty turbo replacement.....Ouch to the wallet.
Keep in mind, this is only my opinion and view, others will swear to a different opinion and view.

 

I agree with Ken. That filter works extremely well.

 

I've gotten crud on my MAF with either the stock Motorcraft paper filter, a Fram (god forbid!) or an oil/cotton filter (K&N, Air Hog, etc).

I can't say either one is any better than any other, in terms of what I see stuck to the MAF wires.

One thing that is a mistake is cleaning a K&N too much. If you leave it, it will filter better and better over time. If that K&N has been on there for years, chances are it's doing the same job as a paper filter, and still flows more.

Your mileage may vary.

 

Tha OEM filter is the best bang for the buck in my opinion

NONE of ANY aftermarket filters will "better flow" or "better filter" the factory paper filter at normal operating RPM and road conditions... If you are racing the V10 or spend a LOT of time at HIGH altitude and 4600 RPM in 2nd gear there is a good argument for the oiled gauze type filters...but for 70MPH cruising at 2100~2250 RPM... they are a waste of bucks

 

I can't argue with that.

 

well, i not only spend a lot of time at high altitude but almost all of my time at high altitude, since i live at 7,000 ft.

i've had the filter in for about a year now. took it out to look at it yesterday, and it certainly has some dirt on it (i used it to tow my trailer for a while and it was off-road quite a bit at that time), but it's not completely gunked over yet. how do i know how dirty is too dirty and time to clean?

i am curious what the good argument for the K&N type filter is at high altitude. so, it seems that i might just be better off leaving it in there?

 

In MY opinion, leave it.

Check inside the air box, after the air cleaner and see if there's any dust in there, that'll tell you how good it's doing. Wipe some off if there is any, drive a few thousand miles and re-check.

As to when to clean? Good question. I'd say, when you notice a power drop-off. But that's very hard to determine.

At high altitude, the air pressure is less. So, the engine is struggling more to get air. With a higher-flowing air filter, the engine can get more air.

 

High altitude almost always also means steeper hill/mountains and this usually includes sections where to keep speed up a lower gear is necessary... the factory filter flows very well through it's entire RPM range... but the aftermarket filters do prove a slight edge at all RPMs above 4600. It is this slight edge in performance that give the K&N type gauze filters the edge and most of the time any negative issues about passing slightly more particulate matter is a non-issue at these elevations... with the exception of eastern Washington state where there is excessively large amounts of Mt Saint Helen's ash everywhere no matter what elevation...

 

I know what you mean about high altitude. I live at around 5500-6200 ft...and travel to the 7000+ ft all the time. With that said, I just use the Motorcraft or NAPA Gold filters. With the miles I put on my V10…I only change it out once a year. Last year I only put on just over 7000 miles.

IMHO...just clean your K&N filter once a year. However, check it every oil change...just to verify its condition. YES...just leave it in. Seems to be working fine for your needs...

As already mentioned...if you are concerned about poor filtering, just purchase a PRE-Charger boot for your K&N.

Good luck...

biz

 

When I bought my 99 F250I installed a K&N I had left over from my 97 F150. I put 33k on it with the F150 and 133,000 in the 99. When it came time to clean the K&N I'd install the stock filter while the K&N dried. With it in there I noticed the truck didn't feel as peppy. With the K&N installed the truck felt normal again. That is the only thing I noticed with the K&N. If you don't know how many miles are on yours then maybe get a cleaning kit and start over.

 

I'd say i have about 12,000 miles on it by now. say...30% off-road. how many miles do you recommend before i clean it?

 

From the K&N web page FAQ:

"The general rule of thumb is that the filter needs to be cleaned when the dirt build up gets as thick as the wire mesh. The usual interval is 30,000 - 50,000 miles depending on driving conditions. We recommend that you check your filter about once a year in normal usage."

http://www.knfilters.com/faq.htm

 

Great post V10man! That's an interesting (and useful) rule of thumb...