2012 Mazda 3 Skyactiv QSUD 0W/20 w/ ceratec

[DBMaster]

Oh, wow. I apologize. I can be more passionate than necessary at times. I realized afterward that you were referring to my 20K oil and not the 7.5K Mazda recommendation. This microGreen thing is an experiment for me. I do think oil is important, but I think it tends to get blown out of proportion, possibly because there are fewer things people can, or will, do on their cars now. My last vehicle had 350K miles on it when I had an accident in it. My daughter's car has 220K miles. So, I have never observed any ill effects from 10K oil changes (with synthetic). I figure even if my UOA doesn't come out that well I'm not going to wreck the engine with this one extended OCI. I got over switching from 3K to 10K back in the 80's.

 

[Brons2]

Originally Posted By: DBMaster
Why not just change it as soon as it starts to turn brown "just to be sure?"


Mine has a nice light brown tint coming right out of the bottle! I better change it again as soon as I drive around the block, right??

 

[DBMaster]

I was being ornery and sarcastic. Not very nice, I know. At 20K miles my oil looks pretty dark, but not really any darker than it looked at 10K. The soot particles that cause this are too small for even the microfilter to catch. That's why, I believe, that many of those bypass filter tests are somewhat misleading. Just add some carbon black of known particle size (large enough to be caught by the bypass filter you are demonstrating, but too small for a full-flow filter to catch) and there you go.

 

[CrawfishTails]

QSUD already has 279 ppm of moly with no Ceratec. So this UOA shows it getting up 465 ppm when it should be 700 ppm if Roble7 used the whole bottle. But the Boron value is way high at 524 ppm when it should be about 29 ppm !

Ceratec alone comes in a 1/3quart bottle, and has 5419 ppm moly and 359 boron. This engine holds 4.4 quarts, so its a 13:1 concentration dilution ratio. QSUD oil 279 ppm moly and only 1 ppm boron.