SkyActiv Oil Analysis Thread

first I've heard about Skyactiv cylinder heads cracking. What are the symptoms when that happens?

Notice on my report that there is barely a trace or even zero for the fuel, water and coolant readings in the oil. So I'm confident my car's engine is still in good shape.
If lucky, maybe oil spots on ground. But with the cover? Otherwise, according to posts, no cluster warnings, maybe alot of smoke, and burnt smell, by but by then who knows how much damage is caused. Some have posted losing a quart per 10 miles. If try to limp it home, you could be out of oil by time get home with it. As soon as see smoke, pull over, let it cool, check oil level, etc. I may permanently pull all those undercovers so I can see what the underside looks like every weekend. And just after fluidfilm the exposed areas. Too late and cold to FluidFilm coat the whole underbody.
 
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careful, sometimes the covers underneath an engine bay help direct air through the radiator. Miatas are known to suffer in the cooling department without the underbody plastics in place.
Definitely gonna put Mazda moly in next time instead of the Castrol Edge.
Apparentlyy the high moly oil is thinner, more moly equals thinner. And with the high pressure, hoping it would push the moly through any hairline cracks to alert me of any problems before warranty expire. Am thinking higher visc oil might not push through until cracks are worse, possibly after warranty. Still got 3 years/60 k miles on PT warranty.
 
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Definitely gonna put Mazda moly in next time instead of the Castrol Edge.
Apparentlyy the high moly oil is thinner, more moly equals thinner. And with the high pressure, hoping it would push the moly through any hairline cracks to alert me of any problems before warranty expire. Am thinking higher visc oil might not push through until cracks are worse, possibly after warranty. Still got 3 years/60 k miles on PT warranty.
I believe you’re over-thinking too much, and you have excellent CPO warranty with 7-year / 100,000-mile powertrain warranty and roadside assistance. Although I use Mazda 0W-20 moly oil, I really don’t believe the moly oil can help anything on cracked cylinder head. You’ll see some warnings if your oil is leaking out to a dangerous level, such as Oil Level Warning Light and Low Oil Pressure Warning Light.

In fact, if the head does have cracked and the oil has leaked out, I’d rather get a whole new engine due to the damaged engine, instead of just replacing the cylinder head.
 
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I believe you’re over-thinking too much, and you have excellent CPO warranty with 7-year / 100,000-mile powertrain warranty and roadside assistance. Although I use Mazda 0W-20 moly oil, I really don’t believe the moly oil can help anything on cracked cylinder head. You’ll see some warnings if your oil is leaking out to a dangerous level, such as Oil Level Warning Light and Low Oil Pressure Warning Light.

In fact, if the head does have cracked and the oil has leaked out, I’d rather get a whole new engine due to the damaged engine, instead of just replacing the cylinder head.
Yeah ...probably. the warrantys there but I buy my cars to run for 10 to 15 years til they fall apart and put money into modifying them.

If this is really due to robotic over-torqued cylinder bolts and cracked heads on 2018 thru 2020 models then this apparently might have gone on for a long time & affected alot of vehicles.

And I would think everything is stamped nowadays and they would have to know which vehicles were affected, especially if it went supposedly has gone on for a few model years. They have to know when they identified the problem and corrected the robots programming.

Which begs the question on something as important as an engine, where is the quality control at to watch the robots apply correct torque? You would think someone would check this every day if not every hour. How could this have happened through multiple years? Surely they didn't crank out the heads in one day/batch. If they did crank em out that quick, they should have been checking robot torque every 5 minutes

And it has to be a waiting game... Eventually it's a matter of time before the combined torque, age and engine pressure cause it to fail. Appears they may play waiting game til it's out of warranty.

Some may crack at earlier mileage or years than others while others might outlast the warranty til have problems.

Even though I really like the way the mazda drives, Will be looking at Ford's over next year and maybe trade this in over next year or two before the warranty runs out.

Checked Carfax, car and driver and consumer reports before purchase and this wasn't on the radar. Only on the forums did these problems come to light.
 
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Yeah ...probably. But I buy my cars to run for 10 to 15 years til they fall apart and put money into modifying them.
Yes you have to be a bit concerned if you’re going to keep the 2018 CX-5 long. I actually cancelled my purchasing plan for a 2018 CX-5 GT AWD when I learned Mazda had added cylinder deactivation to the 2.5L NA.


If this is really due to robotic over-torqued cylinder bolts and cracked heads on 2018 thru 2020 models then this apparently might have gone on for a long time & affected alot of vehicles.
Like the cracked cylinder head issue on the 2.5T, it’s a design flaw which has weak spot on head and cracked at that area by outside force such as going over bumps, not the over-torquing issue by robots.


Checked Carfax, car and driver and consumer reports before purchase and this wasn't on the radar. Only on the forums did these problems come to light.
It’s either way. There’re plenty of car owners don’t come here to report major problems.
 
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Yes you have to be a bit concerned if you’re going to keep the 2018 CX-5 long.

Maybe not keeping that long...
If head cracks after it's out of warranty, its not like you can pick up a used engine at the salvage yard.. they'll all be defective. Would be expensive to replace with new.
Like the cracked cylinder head issue on the 2.5T, it’s a design flaw which has weak spot on head and cracked at that area by outside force such as going over bumps, not the over-torquing issue by robots.

Great. Live in the great pothole state. Main roads are potholed. Side-roads are bumpy /paved unevenly as well as potholes.
 
Here's the report showing the low Moly / high viscosity so the dealer definitely didn't use Mazda oil despite that showing on the invoice. Who knows what they put in there ? and they wonder why some people won't go back to the dealer for service? The Blackstone report identifies the oil as Mazda oil only because I provided that information as per the dealer invoicing.

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The oil viscosity isn't a bad thing. Your engine seems to be in great shape. They suggest to drive 9K miles per change but personally I wouldn't drive that much between changes.
 
⋯ They suggest to drive 9K miles per change but personally I wouldn't drive that much between changes.
IMO, with current oil technology, 9,000-mile oil change interval suggested by BlackStone Lab is not exaggerating and has its base. Toyota has been using 10,000-mile / 12-month OCI with 0W-16 oil for several years. Even Mazda uses 10,000-mile / 12-month OCI on CX-30 and Mazda3.
 
IMO, with current oil technology, 9,000-mile oil change interval suggested by BlackStone Lab is not exaggerating and has its base. Toyota has been using 10,000-mile / 12-month OCI with 0W-16 oil for several years. Even Mazda uses 10,000-mile / 12-month OCI on CX-30 and Mazda3.
Yes, for now, during power-train warranty, doing the 7500 recommended oci, but maybe switch to 9000 oci after warranty period.
 
New report for my 2017 Mazda6. I was worried because I thought the oil smelled like gas, but turned out to not be an issue. Before this fill all I had ever used was the Mazda Moly 0W-20 GF5. I went to the Idemitsu when they didn't come out with a GF6 version of the Mazda branded oil. The current fill is with Idemitsu Ext Mileage GF6, which is supposed to have a higher moly content. I'll get it tested too

Screenshot 2022-02-27 at 09-39-43 document(3) pdf.png
 
New report for my 2017 Mazda6. I was worried because I thought the oil smelled like gas, but turned out to not be an issue. Before this fill all I had ever used was the Mazda Moly 0W-20 GF5. I went to the Idemitsu when they didn't come out with a GF6 version of the Mazda branded oil. The current fill is with Idemitsu Ext Mileage GF6, which is supposed to have a higher moly content. I'll get it tested too
Appears that whatever you are doing, and however you are getting it done, STICK TO THE PLAN. With over 42,000 miles on the clock (at today’s date) I can’t help but think the engine’s longevity may outlast the rest of the vehicle. And at today’s automobile prices? What a blessing that would be.
 
Appears that whatever you are doing, and however you are getting it done, STICK TO THE PLAN. With over 42,000 miles on the clock (at today’s date) I can’t help but think the engine’s longevity may outlast the rest of the vehicle. And at today’s automobile prices? What a blessing that would be.
Yes, dunhillmc’s 2.5L NA without cylinder deactivation in his 2017 Mazda6 should have much better chance that the engine would outlast the rest of the vehicle.

But for other Mazda engines, including newer 2.5L NA with CD、and the 2.5T, I’m not so sure with potential cracked cylinder head and other CD related (non-turbo 2.5L of course) issues.
 
Yes, dunhillmc’s 2.5L NA without cylinder deactivation in his 2017 Mazda6 should have much better chance that the engine would outlast the rest of the vehicle.

But for other Mazda engines, including newer 2.5L NA with CD、and the 2.5T, I’m not so sure with potential cracked cylinder head and other CD related (non-turbo 2.5L of course) issues.
The screwed up part is that with any other vehicle if you engine would blow...just go to junkyard and get one for $800 and plop it in. Not so easy in this case if it blows up out of warranty you'll be on the hook for $$$ thousands (probably between $3000 and $5000) for a new one ... as any in the junkyard will have same problem.
If my 2018 CD cracks/ blows I'm hoping it happens during the warranty period.
 
IMO, with current oil technology, 9,000-mile oil change interval suggested by BlackStone Lab is not exaggerating and has its base. Toyota has been using 10,000-mile / 12-month OCI with 0W-16 oil for several years. Even Mazda uses 10,000-mile / 12-month OCI on CX-30 and Mazda3.
Regarding the OCI, whats the minimum % until you decide to change it?
 
Regarding the OCI, whats the minimum % until you decide to change it?
Let me preface this with, “I’m 73 years old.” Now, every since I was knee-high to a grasshopper, it was drilled into my head, “3,000 miles 3 months, whichever comes first.” Ah, those were the days. No synthetic motor oils. And when they broke onto the motoring scene, I still wasted good money on that old 3,000/3mo belief. Did them myself, so not too badly expensive.

But today? With folks throwing around 9,000 mile intervals? I’m just now getting acclimated to going 5,000/6 months between changes. The entire concept is mind boggling. 🤷🏼‍♂️
 
Let me preface this with, “I’m 73 years old.” Now, every since I was knee-high to a grasshopper, it was drilled into my head, “3,000 miles 3 months, whichever comes first.” Ah, those were the days. No synthetic motor oils. And when they broke onto the motoring scene, I still wasted good money on that old 3,000/3mo belief. Did them myself, so not too badly expensive.

But today? With folks throwing around 9,000 mile intervals? I’m just now getting acclimated to going 5,000/6 months between changes. The entire concept is mind boggling. 🤷🏼‍♂️
Toyota has been using 10K-mile oil change interval for many years, and its engines are still considered as the most reliable among many.
 
my cars lose too much oil to go 10K miles between oil changes. 😂
I changed the oil on my CX-5 at 3,000~3,800-mile interval for the last 2 times.

But it’s not because I want to change the oil more often like in old days, but it’s because the oil life has exceeded 12 months.

This pandemic has really changed many things.

BTW, I just changed the oil on my 2016 CX-5 at 45,872 miles last week as the “Oil change due” message and the red wrench indicator has been on since last December. The indicator was caused by the 12-month oil life, but the oil has only ~3,800 miles when I changed the oil.
 
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