NavyLights

I recently had a used oil analysis performed by Blackstone Labs and thought I would share the results with the forum. I drive an '02 and this oil sample was taken at 40,000 miles after a 6,100 mile oil change interval.

For the past few oil changes I have used Amsoil's 10W-30 ATM Signature Synthetic and Honda's PCX filter. I think my engine must really like this stuff, I didn't have to add a single drop of oil for over 6,000 miles.

This is the first oil analysis that I have had done so I am not too familiar with how to properly translate all of the results. I live in South Texas so the car is subject to a warm climate year-round and it is used as my daily driver with an average trip length between 10 and 15 miles. The car is completely stock, including the air filter.

What do you think?

INDYMAC

Your engine is still in great shape, with a nice tune. Based on other UOA's I've seen for the F20, yours seems to follow a similar wear pattern (virtually none at all). I like the ATM, and have always felt it is the Amsoil flagship lube. No oil consumption in your engine is a big plus and means good ring seal. Without seeing a TAN and oxidation figure for your OCI, it's difficult to say what is optimum. But I think you are OK with 6K miles. How long did it take to drive 6K? I don't know what the starting viscosity was, unless you had a clean sample tested. But it did stay in grade very nicely.

zeroptzero

Nice to see moly back in the additive mix, the anti-wear additive package looks good. Wear metals look good, thanks for sharing the info and posting

starchland

thank you for posting. Do we have a UOA thread to add these to? what air filter?

NavyLights

To answer some of the questions that were asked:

INDYMAC, thank you for your comment. It took 7 months to run through those 6,000 miles.

starchland, I used an OEM air filter that was replaced 2 years ago.

Thanks for everyone's interest!

SpitfireS

According to the Amsoil website, ATM has a TBN of 12.6
What one actually gets out of a bottle will be different, due to production, but how much?
Within 5%?
To see ATM drop to 2.5 in only 7 months / 6k miles is IMO not super duper.
I would have expected more from ATM.
Maybe TBN drops a settles?

What do you mean by didn't have to?
Did you top it up the last X on the dipstick after the change and it dropped to the first after 6k miles?
IOW: you used a quart during the OCI?
Or it didn't use oil at all?
If so you're lucky(*) with an '02.

You could increase the OCI by adding some fresh oil during the OCI - boost the TBN.
If you're engine doesn't use oil this might actually - in this case with this oil! - not be a benefit (*) as the TBN limits your OCI.

Thanks for posting the UOA.

NavyLights

Spitfire S,

You bring up a good point. My engine did burn between 1/2 - 3/4 of a quart over the course of 6,000 miles. I could have added additional oil but chose not to: I wanted to see the results without having diluted or boosted the original 5 quarts. On this next cycle, if consumption is similar, I plan on topping off the oil after a few thousand miles and then extending the change interval to 8,000 miles. Just as you stated, my engine's oil consumption rate should provide a nice opportunity to raise the TBN of the oil near the end of its cycle.

INDYMAC

It is difficult to evaluate the effectiveness of TBN in this formula since there is no TAN data...oxidation and nitration would have been nice too. If you had seen TAN stay or remain within it's original virgin value, then TBN was doing its job and getting depleted=excellent chemistry. Now if TBN dropped to 2.5 and TAN had doubled or tripled=engine oil is depleted and needs replaced. If TBN remains very high and TAN is increasing rapidly=bad chemistry and don't use this product anymore for this application.

rob-2

Why not run longer?

takeshi

I've only performed a couple of UOA's on ATM. FWIW for the first sample TBN dropped to 4.3 after 7,000 miles. For the second sample TBN dropped to 2.6 after 5,000 miles.