The general consensus on oil forums is that high flow gauze and foam air filters result in higher engine wear. I had not fully bought into this line of thinking until perhaps now.

Here is my latest used oil analysis. It shows the UOA results of a run with the stock paper filter and one with a 5 layer gauze cone filter. I am certain that I don't have any air leaks with the gauze cone because I made sure it was well sealed. It's the increase in iron numbers that really bother me.

I did put the stock paper filter back in and will perform another UOA to see if the wear numbers go down.

Discussion thread on oil forum: http://theoildrop.server101.com/foru...e=0#Post853636

 

Which dates are from which filter? The values seem all over the place.

 

08/25 is paper. 03/11 is gauze.

 

I’ve seen much better additive numbers and lower wear with Royal Purple. The calcium (additive) number in the first OCI analysis is very high compared to the second OCI with the same oil; some sort of lab analysis discrepancy? High bearing wear numbers, that’s not from a free flowing filter because you have low silicon. I notice there is no Total Acid Number (TAN) or measurement of sulfate byproducts, you might ask for that additional analysis next time.

 

Not the same oil.
8/25 was the BMW Castrol 5w-30 the dealer uses.
03/11 was German Castrol Syntec 0w-30.

The folks on the oil forum state that you don't have to have high silicon numbers to have wear from dirt getting past the filter.

 

From the looks of it, BMW Castrol is a darn good oil. Your Si numbers didn't change between oil changes so the air filter looks alright. Good to see GC still has a lot of TBN left at 5500 miles.

 

"The general consensus on oil forums is that high flow gauze and foam air filters result in higher engine wear. I had not fully bought into this line of thinking until perhaps now."

It is true. And that is why the use of aftermarket air filters such as K&N will void the Ford warranty. Use at your own risk.

 

so what's the best mix between engine wear and performance... and for that matter what would the safest kind of filter be?

opinions? proof? I know some of you have enough experience to have an opinion on this.

 

Hello
In my MINI I always use the deaer oil here in Portugal (Castrol SLX LL04
0w30).

It is possibel this oil (Castrol SLX) be the German Castrol 0w30? Or the German Castrol is different?

Note: SLX LL04 0w30


Best Regards