Threw away K&N's due to high silicon in UOA's

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The last time I changed the oil in my 03 Ford Ranger and 03 Subaru Forrester I had Blackstone do a UOA on the oil from each. The Ranger oil was Mobil 1 and I ran it 8,022 mi. The Forrester oil was Mobil 1 EP and I ran it 10,973 mi.

The Ranger had about 22,000 mi. on it and the Forrester had about 45,000 mi. on it. I ran a new Pure One oil filter in the Forrester and a new NAPA Gold oil filter in the Ranger. Both vehicles had a new K&N air filter in them.

For the Ranger oil the silicon was 20 ppm and the universal average was 15 ppm. The comments from Blackstone said that the ppm for aluminum, chromium, iron, copper, and lead were "far too high". They ranged from 2 to 8 times higher than the universal averages.

For the Forrester oil the silicon was 21 ppm and the universal average was 11 ppm. Aluminum, chromium, and iron ppm were 3, 2 and 5.5 times the universal averages. The comments from Blackstone said that "High silicon may be dirt getting past the air filter".

Now I can't conclusively blame the high silicon content of the oil and the high engine metals wear on the K&N's, but they are an obvious culprit. It was enough for me to throw away the K&N's and switch back to paper filters. And by the way, neither vehicle showed increased mpg or hp from using the K&N's.
 
Please take them out of the garbage and send them to me. :)

I wouldn't throw them in the garbage until Terry told you do so. I'd get a UOA from him to see if the trended data between the two labs either agrees or disagrees with the assessment that there's too much wear due to dirt ingestion.
 
Enough people have gotten high UOAs back to confirm they let more dirt it, along with test showing pictures of it. I took mine out a while ago on my daily driver and also on the car I co-own because of MAF damage from the oil straight out of the bag.
 
Originally Posted By: ToyotaNSaturn
Please take them out of the garbage and send them to me. :)

I wouldn't throw them in the garbage until Terry told you do so. I'd get a UOA from him to see if the trended data between the two labs either agrees or disagrees with the assessment that there's too much wear due to dirt ingestion.



Sorry, I can't send them to you. They've gone to the dump.

If I can't trust Blackstone, then I can't trust Terry. Sorry, but I think that both do good work, and I trust both. I'm not about to pay to have two reputable labs do the same test of every oil change. In addition, I think that to some extent a cross-check exists by reason of the fact that I got similar results from the UOA of two different vehicles.

As I said in my original post, the two test results do not definitively show that the K&N let too much dirt through and damaged the engines. However, I'm not one to take unnecessary chances. And I've done extensive internet research on the K&N
(which I at first defended) and have concluded that its not worth taking a chance on.
 
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did you have a baseline??? Universal averages arent good enough. A baseline from your application?

I dont doubt that the K&N increases your si levels from dirtingress. But one test is no test. You might have been hasty...

JMH
 
Originally Posted By: jmacmaster
The Ranger had about 22,000 mi. on it

A low mileage engine will show high Silicon readings due to gasket sealers that still "leech" at this time. This is not due to the air filter used.
 
I agree with your decision you did the right thing.

One more potential source of contamination gone.

Stick with OEM filter.

To help get rid of any possible flow restriction across the OEM cold air intake box, I just cut an extra hole (3" diameter approx)in the cold air box on the side behind the headlight area well away from the radiator heat.

The Testers who carried out the famous Air Filter test that showed the ACDelco held most dirt before clogging, clearly stated in that report the OEM paper filter can flow more air than the engine can use as designed. Unless it is heavily modified.
 
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You did the right thing. K&N's are notorious for not filtering as well as oem filters on cars and bikes.
 
Is there an alternative cleanable air filter that filters any better than the K&N? I can't stand paying $50 each time I change my paper air filter. Paper filters should really only cost 5-10$ as far as I'm concerned.
 
Originally Posted By: gto78
Is there an alternative cleanable air filter that filters any better than the K&N? I can't stand paying $50 each time I change my paper air filter. Paper filters should really only cost 5-10$ as far as I'm concerned.


AEM Dryflow. It is better than an K&N in every way. The only problem is I don't think they make as many factory replacements as k&n does.
 
Originally Posted By: gto78
Is there an alternative cleanable air filter that filters any better than the K&N? I can't stand paying $50 each time I change my paper air filter. Paper filters should really only cost 5-10$ as far as I'm concerned.


What type of vehicle are you driving that needs a $50 air filter?
 
I added a AFE oil type air filter to my wifes 97 Jetta...I change the oil and filter at reasonable intervals to worry about silicon.
 
Originally Posted By: ARB1977
I added a AFE oil type air filter to my wifes 97 Jetta...I change the oil and filter at reasonable intervals to worry about silicon.


Cleaning and oiling isnt what affects the silicon, its the cotton gauze filter to begin with.
 
Yup K&Ns are well known in turbo diesel truck circles to let more dirt (silicon) through...
 
I have universal average Silicon numbers with my S&B filter and the outerwears prefilter cover. S&B filters IMO are higher quality than K&N. Must be witchcraft!
 
I used K&N drop-in filter, and when I check my air box, throttle body after 20K, all are clean.
However, my UOA shows high Si even though my car has run 50K.

When I put back the OEM filter, I can feel the acceleration slower, it seems K&N still give lower restriction when the engine sucks air.

The only difference I noticed is the oil getting dirty faster with K&N, and when it hit 10K the oil seems to flow much slower during start-up.
 
Originally Posted By: kr_bitog


When I put back the OEM filter, I can feel the acceleration slower, it seems K&N still give lower restriction when the engine sucks air.

The only difference I noticed is the oil getting dirty faster with K&N, and when it hit 10K the oil seems to flow much slower during start-up.


I'd say that 99% your mind and 1% the air filter.
 
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