Here is the long awaited results from my little experiment.

I basically used M1 and a OEM oil filter for 5200 miles with the OEM Toyota Air fitler, pulled a sample of oil and sent it into Blackstone Labs for them to perform a used oil analysis. I then changed the oil to Amsoil 5W-30 TSL and a Amsoil SDF oil filter and installed the K&N drop in filter. I didn't really notice a seat of the pants difference with the K&N installed. So I ran this oil for 5360 miles and pulled a sample to compare the oils and the air filtration.

So I will post the Numbers side by side of both of the used oil analysis.

THe main number related to air filtration is the silicon values in the used oil. Silicon= Dirt, sand etc. As you can see the results are somewhat of a suprise !
According to these results the silicon values are the same with OEM and K&N filters.

My second UOA was performed by Oil Analyzers Inc.

Here are both of the UOA's
(numbers indicate Parts per million in the oil)
Mobil 1 ---- Amsoil
Aluminum 2 --- 4
Chromium 1--- 0
Iron 10--- 9
Copper 1 --- 2
Lead 1--- 2
TIN 0 --- 0
Moly 84 ---13
Nickel 0 ---0
Silver 0 --- 0
Titanium 0 --- 0
Boron 48 --- 32
Silicon 18 ---18
Sodium 5 --- 8
Calcium 2343 --- 2524
Magnesium 14 --- 705
Phosphorus 665 --- 1015
Zinc 807 --- 1244
Barium 1 --- 0

TBN 3.0 --- 5.74

Visc @ 100C 11.1 --- 12.34

No fuel, water or anti freeze in both samples.

So take it for what its worth. The K&N drop in did not allow any more dirt into my engine at least for now. I put it back in the runner tonight when I got these results. Any questions?

Jake

My biggest fear of claims of increased flow, from aftermarket filters, is that many the actual filtration may be compromised in order to achieve an increase in flow. This is a good indication not my assumption is wrong.

Thanks for sharing that data.

Honestly, this AM, I forgot that I put the k and n back in. So I am driving along and ole blue seemed very peppy this morning. It could of been the cool 62 degree air also, but I think the exhaust note sounds a bit deeper as well. Maybe these filters are more than just hype....?

Thanks for doing all this research!

I've read the K&N filters worse as it gets dirty, while the stock filters better. The oiled gauze clots and forms passages. The stock paper filter needs to load before it filters well.


After 15k on the filters, the results might be different.

How often do you clean the K&N?

So far, I have not cleaned the K and N. I will put some more miles on it and post results on down the road.

Great research! I was getting tired of reading all the negative comments about K&N and I've used them in my past 2 vehicles with both over 100k miles. If anyone ever had a engine hurt by K&N, the word would have been out by auto mags, news, and word of mouth and K&N company would be considered as Shiat.

I think alot of it has to do with the great intake design of the 4 runner, its enclosed, and grabs "cooler" air from the fender area. Its better than most factory intake systems I have owned..

Great results and data about the filter. The amsoil and 4Runner make a lovely couple. You could safely go 12K miles or 12 months with a filter change. I'm using the TSO 0W30 Amsoil with a TRD drop-in and a duel bypass (as you know). I can't wait till I get a UOA on this set-up (7K more miles). If everything goes as planned I'll be happy with 75K on this oil (should get more).

Koz

Drop-in filters won't see much difference in dirt.

Run a K&N FIPK and you will see more silicone + wear.

That's why I went with the TRD drop-in.

Koz

Filters like the K&N actually do a better job when they are 'dirty', and not completely plugged up. It's hard to figure out what is happening with just two uoa's. In stationary engine applications over the past 30 years or so, paper has always been better, especially in dusty conditions. The one best place for oiled elements is in the wet.
Water destroys paper elements. The fact that you are watching the maintenance and being very careful is much more important than the differences between paper and foam in you air filter.

What's more interesting to me than the silicon count is the TBN between the Mobil 1 and Amsoil and nobody has commented on that. I use M1 5W-30 and I'm a bit dissapointed that the Amsoil TBN is almost double the M1, meaning there is significantly more life left in the Amsoil than the M1 at roughly the same mileage.

I wish someone did the same analysis on the V8.

Karl

Maybe you were expecting too much from Mobil 1. I think it's an oil that has a reputation that is a bit better than the oil. Amsoil is a good oil but you have the job of finding a dealer that knows anything about the products. Some are great, some not. I tried Mobil 1 and bailed when I had problems with it shearing out of grade. I have an oil change coming up on my 03 V8 at 30k, but it's coming slower because of the price of gas. I'm driving my 40mpg Civic a lot more.

I can't argue with you there. I'm somewhat new to the oil analysis world. How do you know if it's shearing out of grade?