UOA @12k miles, synthetc vs. regular oil

ZForce

Good UOA's. Any reason for changing out the oil before the recomended oil change interval (OCI) at 3750 mi (yours was at 3K mi)? Lower OCI will normally give better numbers, but I do not think 750 mi would have made a big difference. The silicon has improved but still on the high side (dirt in the air filter) you may want to keep on an eye on the air filter and clean it on a more frequent basis or replace it with a better paper filter.

I have to say this is a very good UOA with only the viscosity breaking down early. Keep paying the extra $10 for the TBN test, its worth every penny. I wish my UOA's were this good.

tranceformer

Why change at 3k miles instead of 3750? Force of habit I guess. And I typically don't do much driving during winter time, so it ends up taking me a while to reach 3k miles. I'm no oil specialist but my guess is that the frequent short trips over the past 6 months might have had some effect on the slight viscosity breakdown.

Update: I'm already up to 1500mi since the last oil change. A few more weeks and I'll have another report on the Castrol Syntec 5w-30.

My Z is up to 12k miles and 1 year of ownership and I'm still running the original factory air filters. It probably wouldn't hurt to change them out now. Thanks for the tip.

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Ray
2009 370Z Base Sport 6MT / 12.860 @ 109.09mph / 1.921 60ft / street tires
official 1/4 mile track times