2017~2024 2.5T Engine Coolant Leaking TSB

sm1ke

2018 Mazda CX-9 Signature
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Canada

Applicable to 2019-2020 Mazda CX-5 GT Reserve and Signature trims (refer to VIN range).
 
Thanks for posting that TSB. My 2019 GT-Reserve falls within the VIN range. I only have about 14,000 miles on the car since buying it new in May of 2019. I'll be on the lookout for spots of coolant on my garage floor and the coolant level in the tank dropping.

Edited to add: I inspected the coolant reservoir last night when the engine was cold. It was maybe just a quarter inch below the top/full mark. I have not added a drop of coolant since I bought the car. So far, so good. But I will continue to monitor for coolant loss and dripping on the garage floor.
 
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Applicable to 2019-2020 Mazda CX-5 GT Reserve and Signature trims (refer to VIN range).
Although the TSB mentioned only cracks on cylinder head for the 2.5T, but the fact is Mazda is replacing the entire engine (or long block) for the problem doesn’t add up. Some members even been told by the Mazda dealer that the crack is on the back side of cylinder block. Either there’re more stories haven’t been told, or there will be more TSBs coming out for this problem.
 
Anyone know how prevalent this is? My VIN is in the range.
This’s a design issue, nothing you can do to prevent it. May be just drive less as the problem just started to show up mostly on earlier CX-9’s with 35K ~ 60K miles.
 
This’s a design issue, nothing you can do to prevent it. May be just drive less as the problem just started to show up mostly on earlier CX-9’s with 35K ~ 60K miles.
Yeah, drive less! That's a good solution. I'll tell my boss I can only come to work three days a week.
 
This’s a design issue, nothing you can do to prevent it. May be just drive less as the problem just started to show up mostly on earlier CX-9’s with 35K ~ 60K miles.

I think he was asking how widespread the issue is, not how to prevent it. Unfortunately I don't think we have exact numbers yet, only a small sample of actual owners who are members of this particular board (or other platforms like FB, but no idea how many of those are reporting the same issue on different social platforms).
 
I think he was asking how widespread the issue is, not how to prevent it. Unfortunately I don't think we have exact numbers yet, only a small sample of actual owners who are members of this particular board (or other platforms like FB, but no idea how many of those are reporting the same issue on different social platforms).
Yeah, sorry read too fast. It’s “prevalent”!

This subject title has to be locked into my head too long!

Poll 2.5T Coolant Leak/Engine Replacement. What can be done to prevent?
 
⋯ Unfortunately I don't think we have exact numbers yet, only a small sample of actual owners who are members of this particular board (or other platforms like FB, but no idea how many of those are reporting the same issue on different social platforms).
Based on the 3-month wait time to get a replacement new engine or long block, and it seems the entire US has run out of the replacement engines, this has to be more common than Mazda expected. The other thing is Mazda says in the TSB that the design of the exhaust manifold gasket and the cylinder head has been modified to reduce the force on the cylinder head which caused the crack. So they’re not comfortable unless newly revised parts, including cylinder head which may not be produced enough quantity at this time, been put into the new engine. They simply just don’t have enough revised parts to produce new engines.
 
Interesting.. I have a VIN that falls within the range on my 2021 CX-5 Signature, but it's production date was 9/20, so it falls outside of the Production Dates listed.. I know it says U.S. Spec and I'm in Canada so I'm guessing I'm safe, but I'm hoping Mazda Canada will release a TSB for us Canadians for clarification.. Or maybe the Canadian models are okay? Either way, I'm glad to see Mazda stepping up and releasing a TSB about this issue. Been following this for awhile.
 
My US Reserve falls within the VIN range but is produced 07/21.
I'm wondering whether they apply production dates just to limit their exposure?
When they say it applies to those produced before Jun. 9, 2020 I hope that it means that they were aware of the issue back then and fixed it?
And not that they fixed it after JM3KF******830243 (VINs are sequential aren't they?) but those with later cars just have to wait for our turn...
 
I start to doubt that VINs are sequential. Mine is JM3KF******4634xx and date of production is 07/21, but they refer to 830243 which is 400k ahead of mine. They produce maybe 100k plus a year? Doesn't add up
 
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I browsed carmax and figured VINs are not sequential, at least across years.There were 6xxxxx produced in 2019, so dates do matter. Hopefully they fixed the engine by 07/21, it would suck to replace engine on the first service visit
 
I don't know if this video has been posted here, but since this is a current topic I found this CX-9 head gasket replacement video interesting. I wasn't aware of any 'coolant plugs' that could leak and how they are covered up and the mechanic goes on to say they should be addressed while apart or it may have to come apart again. It's interesting how Mazda incorporated the exhaust manifold into the head, also this is shown towards the end of the video. It's also amazing the amount of parts removed to replace the head gasket. As always, check out the viewer comments.

 
I don't know if this video has been posted here, but since this is a current topic I found this CX-9 head gasket replacement video interesting. I wasn't aware of any 'coolant plugs' that could leak and how they are covered up and the mechanic goes on to say they should be addressed while apart or it may have to come apart again. It's interesting how Mazda incorporated the exhaust manifold into the head, also this is shown towards the end of the video. It's also amazing the amount of parts removed to replace the head gasket. As always, check out the viewer comments.

Yes, it’s been posted here before in CX-9 forum:

Poll 2.5T Coolant Leak/Engine Replacement
 
New on here. Came looking the other day for the coolant leak, and got the news back from the dealer, $4915 for the repair. Called MazdaUSA and was told because I haven't been taking my CX-5 to the stealer for $75 oil changes, and this is only my 3rd Mazda, they won't cover the repair. That's their policy. If you have been buying a new car every few years, and giving the dealers lots of money, then they 'might' cover the cost of their defective engine.
For a company that is trying to move upmarket to compete with the likes of Lexus and BMW, selling cars that need $5k engine repairs after 60k low stress miles is not a winning strategy.
 
New on here. Came looking the other day for the coolant leak, and got the news back from the dealer, $4915 for the repair. Called MazdaUSA and was told because I haven't been taking my CX-5 to the stealer for $75 oil changes, and this is only my 3rd Mazda, they won't cover the repair. That's their policy. If you have been buying a new car every few years, and giving the dealers lots of money, then they 'might' cover the cost of their defective engine.
For a company that is trying to move upmarket to compete with the likes of Lexus and BMW, selling cars that need $5k engine repairs after 60k low stress miles is not a winning strategy.
So sorry to hear that. Can you tell us the model year and the actual mileage of your CX-5?

It’s hard for Mazda to give every Mazda owner who has major engine problems without powertrain warranty a free fix. I blame it on bad decision making where Mazda decided to modify the a very reliable original cylinder head of the 2.5L NA for the turbo and cylinder deactivation. I can understand the turbo part for more power but they should modify the 2.0L instead of the 2.5L which may provide more space to work on and not to compromise reliability. But modify the head to accommodate the almost useless cylinder deactivation with too many modifications and added components which means too much more complexity? I simply don’t understand it!
 
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