SkyActiv Oil Analysis Thread

As I predicted in my last post/report, after 4K miles the oil level was down to the lower hole on the dipstick. Added a quart to bring it back up to the top mark. So the next time it's down a quart it should be time for my 8K mile oil change.

Do you drive it hard?
 
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CX5 GT
Latest analysis from my 2.5 Non turbo CX5. Not much driving past 6 mo. Mazda Moly 0w20 as usual and oem oil filter.

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The engine runs rich on regular to fight detonation at such a high compression ratio, evidenced by the soot build-up at the tail pipe. If you have that, pull a dipstick and smell the oil. It will have strong gas odor.
Premium fuel does not detonate as readily, so less fueling required to combat detonation. That's how the theory goes.
This should be the case mostly of the cars that see short trips and stop-n-go. At the high RPM/low load highway driving detonation rarely occurs, so less fueling is required, less soot and oil dilution.
That soot at the tailpipe further raises the question about what ends up at the intake valves through EGR and PCV. But no engines had been destroyed because of the valve deposits. Yet?
Thanks for this. I will start with the 91 octane on next fill. Not a fan of E-10, but use the 87 octane with that blend. And I have seen an ever-so-slight amount of “soot” at the pipes.

We do have E-0 in 87, 89, & 91 octanes also available in many of our local stations. Restricted mainly to “Top Tier,” refineries, I believe it is called? But once you cross that ethanol blend to tread into the non-ethanol party, the per gallon prices escalate. And, radically. So, bottom line for me is, “should I,” or “should I not?” I have found in my other vehicles as I fill with the higher priced upper octanes, I seem to benefit in the MPG categories. Kind of a trade-off.
 
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Not much in the comments section. Its pretty standard. The oil can go lot more.
Thanks for this. I’m running 5,000/6 month intervals on factory recommended synthetic viscosity. My dealer doesn’t try to up-sell me on a 3k/3month cycle. That routine died years ago with the advent of these new engines and lubrication improvements, IMO. I also decline any additional recommendations by the service writer. My opinion on what is being serviced? My hip national bank.
 
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2018 CX-5 Sport
I think Blackstone might be in error. I see that no metals are wearing, your aluminum copper and iron are wearing well. If you had antifreeze in the oil I don't think the metal wear would be so good. Have your car tested for peace of mind.
 
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CX5 GT
I wonder whats the oil.Visco is low for only 5k miles.
It seems different oil vs previous UOAs.

Re: coolant - If it was me, I would probably drive a bit then suck some of the new oil with syringe or small pump from the dipstick and send it for 2nd uoa by Polaris to compare.
 
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2015 CX-5 GT
Thank you both, I appreciate the replies.
I did "clean catch" the oil as it left the car. The oil is LiquiMoly SpecialTec AA 5w30. Sharp eye, cz5gt - the oil is different, I was using Mobil1 5w30 previously. I think coolant would account for the thin viscosity, but my current sample (waiting for results) will make that more clear (2600 miles; half the previous interval). I'm also planning to ask them about the "near-zero" results for Molybdenum, Boron, and Magnesium.
Thanks for the tip, DAS - I wasn't aware Polaris offered tests.
 
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CX5 GT
you can check amsoil UOA order page, they use polaris labs but rebrand offer through amsoil. Last time I checked it was a bit cheaper from amsoil.

Polaris also offer something called coolant test but you have to check with them if it may help as a test in your case. Never done coolant tests so not sure what it measures.
 
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2015 CX-5 GT
Thanks for this. I will start with the 91 octane on next fill. Not a fan of E-10, but use the 87 octane with that blend. And I have seen an ever-so-slight amount of “soot” at the pipes.

We do have E-0 in 87, 89, & 91 octanes also available in many of our local stations. Restricted mainly to “Top Tier,” refineries, I believe it is called? But once you cross that ethanol blend to tread into the non-ethanol party, the per gallon prices escalate. And, radically. So, bottom line for me is, “should I,” or “should I not?” I have found in my other vehicles as I fill with the higher priced upper octanes, I seem to benefit in the MPG categories. Kind of a trade-off.
yugrus is right, and I'll build on his comments: A fuel-injected engine will increase mixture and/or adjust timing when a knock sensor activates. This will negate any illusion of savings during fill-up.
Modern engines and fuel systems are designed for up to 10% ethanol; I would buy the highest octane (92/93) E10 fuel available to you. Definitely avoid the new fuels marketed as "Regular 88" and "Unleaded 88" - they are E15. IMO, any high-compression (2.5 Skyactive) or turbo-charged engine should be using a minimum of 89, and 92 is better. I have been using 89 in my 2.5 SkyActive for 90k miles. Stay tuned to my post (above) regarding "possible head gasket" to see if my choice should have been 92!
I'm not a fan of ethanol either, and feel the pain of your (correct) observation when I buy gas for my my "59 Bug (40-50% more expensive). Any amount of ethanol will absolutely destroy the carb/pump/lines (anything rubber) in classic cars. You probably knew that, but I couldn't leave it out.
Another benefit to Premium blends is that they often contain other additives that act as cleaning agents to the entire fuel system.
 
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yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
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Plano, Texas, USA
Thank you both, I appreciate the replies.
I did "clean catch" the oil as it left the car. The oil is LiquiMoly SpecialTec AA 5w30. Sharp eye, cz5gt - the oil is different, I was using Mobil1 5w30 previously. I think coolant would account for the thin viscosity, but my current sample (waiting for results) will make that more clear (2600 miles; half the previous interval). I'm also planning to ask them about the "near-zero" results for Molybdenum, Boron, and Magnesium.
Thanks for the tip, DAS - I wasn't aware Polaris offered tests.
It’s very strange indeed that the content of molybdenum is almost non-existent from LiquiMoly SpecialTec AA 5w30. It’s 600 ~ 700 from Mazda moly 0W-20 oil.
 
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2013 Mazda CX-5 Sport FWD Auto
Its
It’s very strange indeed that the content of molybdenum is almost non-existent from LiquiMoly SpecialTec AA 5w30. It’s 600 ~ 700 from Mazda moly 0W-20 oil.
Its bizarre. Either the oil isn’t made as advertised, or (fingers crossed) a sample was accidentally swapped at Blackstone. This may be a result from somebody else’s sample.
 
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2013 Mazda CX-5 Sport FWD Auto
LiquidMoly is their brand name only. There is nothing on the labeling that says it is a high moly oil
The UoA says 1 for Moly. LiquidMoly per the manufacturer claims it contains MoS2, hence the name. A reading of 1 is practically non existent.
 
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CX5 GT
I think not all type of that oil have Moly.
My opinion, for the price of that oil vs Mazda oem, I would stick with Mazda oem.