Poll 2.5T Coolant Leak/Engine Replacement

Who is having coolant leak issues and have had their engines replaced?

  • Yes

    Votes: 46 39.0%
  • No

    Votes: 72 61.0%

  • Total voters
    118
Will do. I will get exact number in the morning but it was a touring. MSRP 38,700. Sell price was approx 37,100 plus $150 doc,. I got it from Everett Mazda, WA. No sales tax because it going to my home state of Alaska. And I do the registration when it gets up there. 100 for the reg, 15 title. And all that money I saved goes to AML to ship it up there. $1925 (ouch). Oh well. Pretty happy with the new car.
 
I'm going to start another thread...
You shouldn’t try to purge the air from coolIng system by yourself with the engine just got replaced by your Mazda dealer. Not only the potentially HOT coolant will overflow from the radiator neck without the cap which is dangerous like the warning stated on the radiator cap unless you have that special kit mentioned by Kedis82ZE8, but also you’d lose expensive FL22 coolant (don’t use any other coolant other than the Mazda OEM FL22) and need to buy a gallon to top off which may cost you some money. Just find some time and take the CX-9 back to your Mazda dealer and let them fix the problem.
 
I am Just wondering if the 2022 CX9 engines have been updated so this is no longer a problem. And curious what the problem was
The cracked cylinder head problem from both the 2.5L NA with cylinder deactivation and the 2.5T with turbo IMO is because the cylinder head was modified from the original cylinder head on the 2.5L without CD. The modification for CD and turbo somehow weakened the head in certain areas which caused the crack. Even if Mazda claimed they had modified the cylinder head again on the 2.5T which should have reinforced the weakened area, I’d still have some doubts that why could they modify the head this way at the first place when they redesigned the head for the 2.5T? And how long this new modification can hold up since Mazda had failed the same task at the first place? There always have limitations and restrictions when you modify something but not design the thing from scratch. That’s why I personally will not consider both the 2.5L NA with CD and the 2.5T from Mazda since I usually keep my vehicle for as long as I can and the longevity is my number 1 priority.

Now I read the later posts that you’ve just purchased a new CX-9, I can only say congratulation to you and hope for the best.
 
⋯ Mazda cannot afford to make a massive error that could cost them dearly in the long run. Since the 2.5T is in everything aside from the CX-3 and MX-5 and will see widespread use in the new CX-50 in North America as well now they will have gotten this issue resolved very quickly.
Mazda did make a big mistake by insisting their problematic and unreliable rotary engines in production line which was the major reason causing them near bankruptcy and relied on Ford to rescue them.

Nobody really knows the cracked cylinder head issue has been resolved from root until another 5+ years and 50K+ miles. After all it took at least that much time to expose the issue with original head on the 2.5T which was modified from the “original” head used on the 2.5L NA without cylinder deactivation. See the reasoning stated in my previous post.
 
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Mazda did make a big mistake by insisting their problematic and unreliable rotary engines in production line which was the major reason causing them near bankruptcy and relied on Ford to rescue them.

Nobody really knows the cracked cylinder head issue has been resolved from root until another 5+ years and 50K+ miles. After all it took at least that much time to expose the issue with original head on the 2.5T which was modified from the “original” head used on the 2.5L NA without cylinder deactivation. See the reasoning stated in my previous post.
This thread isn't about decisions Mazda made in the past, I'm talking about Mazda as a whole today, but for argument sake, the Rotary is something Mazda was known for and is a significant part of their heritage, it helped them to become the first Japanese OEM to win at Le Mans and is widely regarded as amazingly powerful and tunable when done right. In my opinion, it truly has a unique personality that can't compare to any other engine design. There are tons of people who love the design and the sound. I agree that it may not be the most reliable engine or the most efficient and definitely not an engine for your average econobox production vehicle, but without Mazda's dedication to that design and mass production, it would have not made it into the (relatively) modern day RX-7 and RX-8 as well as Le Mans racers. When applied to the right use, it has it's place and personally I'm glad they developed it to the level they did, It made Mazda stand out as a unique Automotive Manufacturer, things could have been different maybe, for the better, or worse but I think overall it was a positive decision that helped build the character Mazda is known for today.

To me, It's pretty clear from what I read in the TSB that Mazda has found a cause and resolved it. Which if you read about the other TSB for this engine in regards to the low oil levels some owners have been experiencing, they haven't found a real cause to that yet and stated so but have admitted to making changes to the engine that may have affected it. So internally there must have been investigations that led to this conclusion and I would trust the TSB for the head cracking issues. This to me isn't just a Band-Aid fix.

Now yes, it's still a newer engine design and it has to take on the test of time, which, admittedly is why I waited until 2021 to buy in.. But in my research before buying I read about, and found several high mileage Gen 2 CX-9's out there with well over 150k+ on them with all original engines that only ever needed routine services, as well as from chats with my local dealership parts advisor about CX-5's/CX-9's the dealership service department has seen. If I knew about this failure sooner, before I bought in, It may have changed my mind, but I am happy that I'm safe with my 2021. As I stated, I don't think Mazda as a company can afford to mess this up long term, so it's in their best interest to not be taking on thousands of warranty claims for something as catastrophic as this issue can turn out to be, especially in this market as well. They learnt a lot from their 2.3T DISI MZR engine from the mid 2000's and the mistakes made with that.
 
This isn't really rocket science. Been a mechanic all my life and the tsb is pretty straight forward. The tsb is saying that the head was not designed correctly and has been now redesigned to fix the problem. I guess my question might be how soon on average were the failures on the first version head and how does that compare to the second version head? Any forum members have this failure on the second version?

One member says: "There always have limitations and restrictions when you modify something but not design the thing from scratch.:

I think you have it backwards. If it's designed from scratch you have no experience or information of how it will stand the test of time. If you revise or update an existing part you are focusing on its weak areas. Just my opinion
 
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First failure are typically around the 60k mark, 3-4 years. If i recall correctly there is a handful of 2018 on this forum with a cracked engine and maybe a 2019? The rest seems to be mainly 2016s for now. So we will have to wait another 2-3 years before we can say if this issue will show up on 2021s.
 
After more investigation and a call to my local dealer, I was able to get my hands on the service history. The large time and low mileage gap in the service history for my CX-9 was not for an engine replacement. Just did the 60k oil change last weekend. No signs of coolant leaks; no noticeable coolant in the oil and no low coolant. According to what @youri has surmised, if I am to get a leak, it would most likely be this oil change or one of the next two. Sample has been sent off for analysis to see if maybe there is coolant in the oil.
 
This thread isn't about decisions Mazda made in the past, I'm talking about Mazda as a whole today, but for argument sake, the Rotary is something Mazda was known for and is a significant part of their heritage, it helped them to become the first Japanese OEM to win at Le Mans and is widely regarded as amazingly powerful and tunable when done right. In my opinion, it truly has a unique personality that can't compare to any other engine design. There are tons of people who love the design and the sound. I agree that it may not be the most reliable engine or the most efficient and definitely not an engine for your average econobox production vehicle, but without Mazda's dedication to that design and mass production, it would have not made it into the (relatively) modern day RX-7 and RX-8 as well as Le Mans racers. When applied to the right use, it has it's place and personally I'm glad they developed it to the level they did, It made Mazda stand out as a unique Automotive Manufacturer, things could have been different maybe, for the better, or worse but I think overall it was a positive decision that helped build the character Mazda is known for today.
Yes, Mazda’s rotary engine was legendary at the time, but they shouldn’t keep it in production into late 1980’s when the engine apparently couldn’t keep up the power output、fuel efficiency、and emission standard (because the natural of rotary engine design which needs to burn oil like the 2-cycle engine), in addition to reliability issue. That’s the big mistake Mazda made.


To me, It's pretty clear from what I read in the TSB that Mazda has found a cause and resolved it. Which if you read about the other TSB for this engine in regards to the low oil levels some owners have been experiencing, they haven't found a real cause to that yet and stated so but have admitted to making changes to the engine that may have affected it. So internally there must have been investigations that led to this conclusion and I would trust the TSB for the head cracking issues. This to me isn't just a Band-Aid fix.
Unless you’re an engineer working for Mazda HQ in Japan, you really don’t know the problem of cracked cylinder head has really got resolved. Even those Mazda engineers don’t really know for the next several years until proven, or they’d have prevent this problem at the first place when they revise the head from original 2.5L NA without CD.

For example, when the rear brake dragging issue on my 2016 CX-5 with EPB was first exposed, Mazda came out a TSB to replace the EPB control module apparently with updated software trying to eliminate the problem ONLY in cold climate. The 2nd TSB then issued later with another updated EPB control module. Then the 3rd TSB finally came out which would replace the rear disk calipers instead of EPB control module. Based on the final TSB apparently the inconsistency on tolerance during manufacturing process to a screw used by EPB within the caliper is the true culprit, and the entire caliper needs to be replaced with the revised version.


Now yes, it's still a newer engine design and it has to take on the test of time, which, admittedly is why I waited until 2021 to buy in.. But in my research before buying I read about, and found several high mileage Gen 2 CX-9's out there with well over 150k+ on them with all original engines that only ever needed routine services, as well as from chats with my local dealership parts advisor about CX-5's/CX-9's the dealership service department has seen. If I knew about this failure sooner, before I bought in, It may have changed my mind, but I am happy that I'm safe with my 2021. As I stated, I don't think Mazda as a company can afford to mess this up long term, so it's in their best interest to not be taking on thousands of warranty claims for something as catastrophic as this issue can turn out to be, especially in this market as well. They learnt a lot from their 2.3T DISI MZR engine from the mid 2000's and the mistakes made with that.
The 6-year-old 2.5T is not new and it’s based on even older (10 years old) 2.5L NA without CD. The problem is only the cylinder head which was revised for the turbo and cylinder deactivation. It took more than 4 years for Mazda to realize the seriousness of the design flaw, and made the modification to the head. The question is still the revised head hasn’t been tested long enough for its longevity, and only time will tell.

For a major problem like this we should look at the probability of the failure rate, not a few examples which run fine with high mileage. Even the worse car will have some running fine for long period of time, but the majority of it may have already done for its service life.
 
⋯ One member says: "There always have limitations and restrictions when you modify something but not design the thing from scratch.:

I think you have it backwards. If it's designed from scratch you have no experience or information of how it will stand the test of time. If you revise or update an existing part you are focusing on its weak areas. Just my opinion
Not saying this has caused cracked cylinder head, bit here’s an example of limitations and restrictions when you revise an original cylinder head for cylinder deactivation: Your have to make the bore bigger than original on cylinder #1 and #4 to accommodate bigger switchable hydraulic lash adjuster (HLA), but is this will weaken the structure in that area of the head? If you design a head from scratch, you can put that in consideration and design a way to reinforce the area for bigger bore but still keeping the head compact.

With more than 100+ years of experience designing an ICE, added by CAD CAM nowadays, engine design is not that difficult like it used to. But making it small、compact、and efficient is a challenge.
 
I think this engine would be fun to own, but my bias against turbos and all the issues would keep me from getting it. I like cars that go 200k+, I don't know if turbo engines have that longevity.
My 08 civic 4 cylinder non turbo has almost 180k mi so will the 2nd gen CX-5 / CX-9 Turbo get there trouble free?

Btw any cx-5 / cx-9 Turbo owners hit that range yet?
 
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My 08 civic 4 cylinder non turbo has almost 180k mi so will the 2nd gen CX-5 / CX-9 Turbo get there trouble free?

Btw any cx-5 / cx-9 Turbo owners hit that range yet?
I have a 2010 civic with 241k on it. your 08 is barely broken in. That generation civic is by far one of the best ones out there. My friends 2006 has 350k on it. I don't know of many Mazda owners getting that kind of life expectancy.
 
Yes it can last longer than 180k. One in this thread had the coolant leak happen at 230k i believe. But This thread is getting out of hand. Please try to keep the discussion to the issue in topic. We can start another thread about engine reliability if needed.
 
Just got my 2016 CX9 68k miles sent in to the dealership last week and quote came back at $7800 to replace the entire engine. They are writing a preauthorization to Mazda to see what's manufacturer is able to help, finger crossed , hope they cover in full with min. Deductible

What's funny is that, I own a 2009 RX8 as well, never thought the RX8 outlast the CX9
 

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Just got my 2016 CX9 68k miles sent in to the dealership last week and quote came back at $7800 to replace the entire engine. They are writing a preauthorization to Mazda to see what's manufacturer is able to help, finger crossed , hope they cover in full with min. Deductible

What's funny is that, I own a 2009 RX8 as well, never thought the RX8 outlast the CX9

Sorry to hear :( How does the oil on the dipstick look?
 
Just got my 2016 CX9 68k miles sent in to the dealership last week and quote came back at $7800 to replace the entire engine. They are writing a preauthorization to Mazda to see what's manufacturer is able to help, finger crossed , hope they cover in full with min. Deductible

What's funny is that, I own a 2009 RX8 as well, never thought the RX8 outlast the CX9
Definitely hate to hear someone else is dealing with this.

Please remember to report your situation to the NHTSA.

Here’s the thread below:

Thread '2.5T Cracked Cylinder Head/Leaking Coolant Report to the NHTSA'
https://mazdas247.com/forum/t/2-5t-...eaking-coolant-report-to-the-nhtsa.123877405/
 
I have a 2010 civic with 241k on it. your 08 is barely broken in. That generation civic is by far one of the best ones out there. My friends 2006 has 350k on it. I don't know of many Mazda owners getting that kind of life expectancy.
My sister sold an early 80s Mazda (GLC?) with over 300,000 miles on it and was still running great.
One of the reasons more 300K+ Japanese vehicles are not still on the street is the length of time factor. Once a vehicle reaches a certain age, gaskets tend to start leaking. Some gasket replacements cost more than $1000 and by the time they need replacing, the car is not worth enough for the owner to spend that kind of money having it repaired. This was the case with my 1989 MX6 GT. The engine was rock solid but leaky gasket replacements would've set me back $2000. That car's odometer never passed 150,000 miles for that reason.
 
Definitely hate to hear someone else is dealing with this.

Please remember to report your situation to the NHTSA.

Here’s the thread below:

Thread '2.5T Cracked Cylinder Head/Leaking Coolant Report to the NHTSA'
https://mazdas247.com/forum/t/2-5t-...eaking-coolant-report-to-the-nhtsa.123877405/
That NHTSA reporting is done. Dealer call back today , they slash the bill from $7800 to $2600 with Mazda backing.... pretty sure this dealership toss in some extra parts and hours. But I need my car back so just banking on a later recall , hopefully the balance will be paid back to me later
 
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