2021 CX-9 Burning oil

Did the dealer change it?

I wonder what brand of oil.
Yes, the dealer changed it a two months ago. I checked it right after it was changed and it was above the top hole. I have been checking it every 1000 miles or so. I do feel that it has gone down more from 4000-5000 miles than it did from 0-4000. I am going this afternoon to have the dealer do the oil change and will show them this pic and also the TSB. I have had my light come on twice as well so they are aware.
 
So, I am scheduled to get my oil changed today. The car has 5039 miles from the last oil change. At the start, the oil was slightly above the top hole. This is it this morning.

View attachment 305372
I just want to clarify the distance is not proportionate to the amount of oil you have. You'll probably need 1/4 quart to bring it up to top mark.
 
From bottom hole to top hole it is 1qt, so you are a half of a quart low

When my low oil warning light has come on, it was just slightly below this level. And when I added a quart of oil, it went to slightly above the top hole - to basically where it is right after a fresh oil change.

Currently, the low engine oil warning light it not on. But I think if I tried to go another 500 miles, I bet it would come on.
 
So, I took the car in and the service guy tried to say that that level was normal as the normal level comes right in the middle of the two dots. I did tell him that I looked at the oil level right after the last oil change and it was right above the second hole. This is what it looks like now after this oil change (it is thin so you can barely see the line right above the last dot).
IMG_9751 copy.jpg
 
I was thinking of trying the SP verision of Idemitsu 5w30.
So, I am scheduled to get my oil changed today. The car has 5039 miles from the last oil change. At the start, the oil was slightly above the top hole. This is it this morning.

View attachment 305372
Honestly that's not that bad. Ideally, we all want it to stay at the very top, but in many cars that's just not the case. How do you drive? Asking because if you drive fast or in the upper rpm range a lot, there is a good chance you may some oil consumption. Oil consumption has a lot of different factors. Skyactiv engine have historically shown to be one of the better 4cylinder engines that generally don't consume excessive amounts of oil.
 
I was thinking of trying the SP verision of Idemitsu 5w30.

Honestly that's not that bad. Ideally, we all want it to stay at the very top, but in many cars that's just not the case. How do you drive? Asking because if you drive fast or in the upper rpm range a lot, there is a good chance you may some oil consumption. Oil consumption has a lot of different factors. Skyactiv engine have historically shown to be one of the better 4cylinder engines that generally don't consume excessive amounts of oil.

This is abnormal. I have had a 2014 CX-5 (2.5 NA), a 2018 CX-9 with the 2.5T, a 2017 Mazda 3 (2.0 NA) along with our 2021 CX-9 and CX-5 (both with the 2.5T). I routinely check my oil and none of those other cars changed any over a 3-5K period. Same is true for the roughly 20 other cars that we have had over the years. The lone exception being my 1971 MGB!

The 2021 cars burn oil, so much that the low oil warning light will come on after 5000 miles. The TSB matches exactly what I see (our cars have the indicated VIN numbers as well).
 
I'd start using a better quality oil than what the dealer probably uses. The big drop from 4000 to 5000 miles might mean the oil was losing volatiles via the pvc or elsewhere.

If you have a problem with the valve stems or other oil control parts using a better oil could help reduce the loss and also give better lubrication until you or Mazda can correct that problem.
 
I'd start using a better quality oil than what the dealer probably uses. The big drop from 4000 to 5000 miles might mean the oil was losing volatiles via the pvc or elsewhere.

If you have a problem with the valve stems or other oil control parts using a better oil could help reduce the loss and also give better lubrication until you or Mazda can correct that problem.

Thanks. I will try that. They are using Mazda Synthetic right now. I also noticed that they reset the service interval from the 7500 mile interval to 5000 miles. In the TSB, Mazda thinks that "
valve stem seal damage is causing oil to leak into the combustion chamber". Would a thicker oil help the seal?
 
Thanks. I will try that. They are using Mazda Synthetic right now. I also noticed that they reset the service interval from the 7500 mile interval to 5000 miles. In the TSB, Mazda thinks that "
valve stem seal damage is causing oil to leak into the combustion chamber". Would a thicker oil help the seal?
Be aware that OEM https://www.amazon.com/dp/ (commissions earned) is totally different from https://www.amazon.com/dp/ (commissions earned). OEM Mazda 5W-30 oil is the same as Castrol GTX which is NOT full synthetic, and it's also a GF-4 oil which is not recommended to use by Mazda.

A4C4E2A2-85FC-4E01-8B70-367664EAD448.jpeg


All name-brand 5W-30 oils even Costco’s Kirkland oil now meet the latest SP / GF-6 specifications. If valve stem seals are physically worn or damaged which caused oil consumption, even the best oils can’t save them. Seals need to get replaced.
 
Some oils do help reduce seal leakage. How well might depend on the type and cause of the seal damage, which apparently has yet to be discovered.

If they're using that conventional or semi- synthetic oil I would change it at 4000 miles, since that is the point where the consumption increases.

I would be trying to keep the oil consumption down until the cause is remedied, because the extra oil in the combustion chamber is not a good thing, no matter what the cause.

Higher RPM might also aggravate the problem, especially while going down hill, which can increase the vacuum and pull more oil through the valve stems.
 
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Some oils do help reduce seal leakage. How well might depend on the type and cause of the seal damage, which apparently has yet to be discovered.
FWIW:

Oil used to seep past the turbocharger seals in my late '06 Mazdaspeed6 due to inadequate crankcase ventilation while idling that pushed oil past the turbine seals. This resulted in bluish smoke coming out the tail pipe (oil getting burnt off).

I temporarily addressed the issue by raising oil viscosity from 5w-30 to 5w-40, before I got the proper fix done. This worked well.
 
"OEM Mazda 5W-30 oil is ... a GF-4 oil which is not recommended to use by Mazda."
I don't think any oil company is blending a GF-4 oil now. It'll all be GF-6A which is completely backward compatible.

I have no idea what oil is actually in a Mazda branded bottle. As mentioned above, it may very well be made by Castrol, which is fine for what it is. The dealership probably has a bulk oil tank and gets a tank truck of oil (or 55 gallon drums or 275 gallon tote) of which ever brand gave him the lowest price for the current yearly contract. It will be the minimum quality allowed by the warranty. And it'll be good enough for almost all the customers. A full synthetic gives us who plan on owning the car a very long time some edge...and I'm not differentiating between a Group 3 base oil or Group 4 base oil. I would not use a higher viscosity grade oil in cold winter areas. 5W-40 in a Phoenix summer...I think it's a good idea. Not in a Minnesota winter.

There is one product that will do a good job of cleaning carbon from rings and seals if that is the cause of the oil leaking by and getting burned. Auto-Rx is an ester based 4000 mile engine cleaner that has worked well for me in the past. Of course if there are damaged parts, nothing in a bottle will help that.
 
"OEM Mazda 5W-30 oil is ... a GF-4 oil which is not recommended to use by Mazda."
I don't think any oil company is blending a GF-4 oil now. It'll all be GF-6A which is completely backward compatible.
I actually went to my Mazda dealer and checked out this OEM https://www.amazon.com/dp/ (commissions earned)https://www.amazon.com/dp/ (commissions earned)a couple of years ago. The description on the back does say GF-4. And the parts guy who has been working for this one of the oldest Mazda dealers in Dallas area all his life told me Mazda says it’s made by Castrol and it’s the same oil as GTX which is a conventional oil.

Here’s an example a CX-5 owner with 2.5T did an oil change at his Mazda dealer. The invoice says the oil used is Mazda OEM 0000-78-5W30-BK (bulk?) and the service claimed it’s full synthetic. After pushing for proof, the parts manager admitted it’s NOT full synthetic. Ended up the Mazda dealer not only replaced the OEM Mazda 5W-30 oil with full synthetic 5W-30 oil and a new OEM oil filter, but also gave him and his wife 3 free oil changes!

Mazda Moly Oil in 5W-30: Does It Even Exist?

So Mazda OEM 0000-78-5W30-BK oil which replaces 0000-77-5W30-BK oil which is the same Genuine Mazda SAE 5W-30 Super Premium Motor Oil 0000-77-5W30-QT in bottle, is still not full synthetic. I’ll never use an oil which is not full synthetic if I have a turbo. Have seen too many issues due to the extremely high temperature on turbo with conventional oils.
 
I actually went to my Mazda dealer and checked out this OEM https://www.amazon.com/dp/ (commissions earned)https://www.amazon.com/dp/ (commissions earned)a couple of years ago. The description on the back does say GF-4. And the parts guy who has been working for this one of the oldest Mazda dealers in Dallas area all his life told me Mazda says it’s made by Castrol and it’s the same oil as GTX which is a conventional oil.

Here’s an example a CX-5 owner with 2.5T did an oil change at his Mazda dealer. The invoice says the oil used is Mazda OEM 0000-78-5W30-BK (bulk?) and the service claimed it’s full synthetic. After pushing for proof, the parts manager admitted it’s NOT full synthetic. Ended up the Mazda dealer not only replaced the OEM Mazda 5W-30 oil with full synthetic 5W-30 oil and a new OEM oil filter, but also gave him and his wife 3 free oil changes!

Mazda Moly Oil in 5W-30: Does It Even Exist?

So Mazda OEM 0000-78-5W30-BK oil which replaces 0000-77-5W30-BK oil which is the same Genuine Mazda SAE 5W-30 Super Premium Motor Oil 0000-77-5W30-QT in bottle, is still not full synthetic. I’ll never use an oil which is not full synthetic if I have a turbo. Have seen too many issues due to the extremely high temperature on turbo with conventional oils.
Good find! I agree I would only use a full synthetic in a turbo. I had assumed (mistake lol) that it was the same as the Idemitsu SP 5w30, which appears good on paper.
 
I actually went to my Mazda dealer and checked out this OEM https://www.amazon.com/dp/ (commissions earned)https://www.amazon.com/dp/ (commissions earned)a couple of years ago. The description on the back does say GF-4. And the parts guy who has been working for this one of the oldest Mazda dealers in Dallas area all his life told me Mazda says it’s made by Castrol and it’s the same oil as GTX which is a conventional oil.

Here’s an example a CX-5 owner with 2.5T did an oil change at his Mazda dealer. The invoice says the oil used is Mazda OEM 0000-78-5W30-BK (bulk?) and the service claimed it’s full synthetic. After pushing for proof, the parts manager admitted it’s NOT full synthetic. Ended up the Mazda dealer not only replaced the OEM Mazda 5W-30 oil with full synthetic 5W-30 oil and a new OEM oil filter, but also gave him and his wife 3 free oil changes!

Mazda Moly Oil in 5W-30: Does It Even Exist?

So Mazda OEM 0000-78-5W30-BK oil which replaces 0000-77-5W30-BK oil which is the same Genuine Mazda SAE 5W-30 Super Premium Motor Oil 0000-77-5W30-QT in bottle, is still not full synthetic. I’ll never use an oil which is not full synthetic if I have a turbo. Have seen too many issues due to the extremely high temperature on turbo with conventional oils.
That was me. Feeling famous :)
 
Anyone had their vehicles fixed yet from this TSB?

My 2018 cx9 GT doesn't burn oil at all.. Sitting at 78k kms now.

Used the Castrol Edge mostly with decent results. Been using the in Pennzoil platinum last few oil changes-- will likely try the ultra platinum on the next oil change but I don't expect it to be much different as I assume a few extra cleaning properties.

My biggest gripe with the car has been the excessive vibrations, which is now fixed-- on another thread.

GL with the burning-- definitely annoying as it'll be at the front of your mind when driving... Esp since most of us bought the vehicle because of the driving characteristics.
 
Anyone had their vehicles fixed yet from this TSB?
This oil consumption issue described in the new oil consumption TSB is only for 2021 2.5T:

TSB No.: 01-012/21 CHECK ENGINE LIGHT ON WITH DTC P250F:00 DUE TO LOW ENGINE OIL LEVEL

Mazda said in the TSB “the root cause of this concern has not been identified yet, therefore a repair procedure will be announced at a later date”, but actually seemed to know the cause and said “since this issue has been reported after a valve stem seal modification, it is very likely that valve stem seal damage is causing oil to leak into the combustion chamber”.

If the 2.5T does show low oil level and no oil leakage is found, topping off the engine oil to the FULL level is the only thing Mazda dealer will do at this time as a temporary measure.
 
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Anyone had their vehicles fixed yet from this TSB?

My 2018 cx9 GT doesn't burn oil at all.. Sitting at 78k kms now.

Used the Castrol Edge mostly with decent results. Been using the in Pennzoil platinum last few oil changes-- will likely try the ultra platinum on the next oil change but I don't expect it to be much different as I assume a few extra cleaning properties.

My biggest gripe with the car has been the excessive vibrations, which is now fixed-- on another thread.

GL with the burning-- definitely annoying as it'll be at the front of your mind when driving... Esp since most of us bought the vehicle because of the driving characteristics.

This TSB only applies to 2021 vehicles. Your 2018 CX-9 is not impacted by this in any way and that is the main reason your car does not burn oil. It most likely has nothing to do with the type of oil.

As for the 2021 models, there is no fix yet. And I would think there may not be one in the short term. I would also bet that if there are engine failures they will deal with them on a case by case basis - like they are doing with the coolant issue. Personally, I am hesitate to keep this long term and will most likely trade it in for something else within a year or two.
 
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