If you’re a Mazda vehicle owner that is equipped with the SKYACTIV-G 2.5T engine, it’s important to be aware of a class action lawsuit recently filed that could significantly impact you.
The law firm of Sauder Schelkopf filed the action Jarvis et al. v. Mazda Motor of America, Inc., et al., that alleges a defect with the engine’s cooling system may cause engine stalling and catastrophic engine failure.
According to the complaint, the alleged defect affects a range of popular Mazda models including the CX-5, CX-9, and Mazda6.
Naturally for many Mazda owners, this defect has sparked concerns over vehicle safety, reliability, and the integrity of Mazda’s engineering.
In this article, we delve into the intricacies of the alleged engine coolant defect. We’ll uncover what every Mazda owner with the SKYACTIV-G 2.5T engine should know.
The Mazda Engine Coolant Defect Lawsuit at a Glance
This issue revolves around the engine cooling system with Mazda vehicles equipped with the SKYACTIV-G 2.5T engine. As one can imagine, the implications of a cooling system defect are severe.
The potential outcomes of this defect range from engine overheating, to catastrophic engine failure. Both which are not only costly to repair, but also a safety concern.
The plaintiffs, a group of affected Mazda owners, argue that Mazda failed to adequately inform owners about the defect, despite knowing its potential for harm. As a result, a class action lawsuit has been filed against Mazda Motor of America, Inc., and Mazda Motor Corporation.
The plaintiffs have taken this step to hold Mazda accountable for not only the financial burden caused by this defect, but also for the potential danger it poses to all road users.
The Core of the SKYACTIV-G 2.5T Engine Coolant Defect
The engine cylinder head is an integral part of the engine structure and combustion cycle. One function of the cylinder head is to close the top of the combustion chamber.
The cylinder head is bolted to the top of the engine block thereby sealing the combustion chamber where the combustion cycle takes place.
The cylinder head also contains coolant passages–which flow significant amounts of engine coolant. A functioning coolant system is vital for maintaining safe and steady engine temperatures. Heat generated during the combustion cycle needs to be transferred away from the engine. This process prevents the engine from overheating.
The Mazda SKYACTIV-G 2.5T defect in question arises from the engine’s cylinder head area around the exhaust manifold. This is where significant structural weakness has lead to engine coolant leakage, as seen in the picture below.
The lawsuit alleges that this leakage can result in overheating, engine damage, and eventual engine failure. Simply put, this defect has a severe impact on the engine’s ability to function properly.
The lawsuit alleges that the cylinder head’s structural weakness stems from both manufacturing and design flaws. This particular area of the engine is subject to high heat and stress, which, coupled with inadequate design, leads to material fatigue and eventual failure.
According to Comsol, material fatigue is when a material gets damaged from being repeatedly stressed. This in turn eventually causes the material to fail and crack, as with the case with the SKYACTIV-G 2.5T cylinder head.
The situation is exacerbated by the fact that these cracks in the cylinder head develop unexpectedly over time, leading to sudden and severe consequences.
Financial and Environmental Implications of This Defect
Repairing this defect is not only expensive but also complex. In most cases, the entire engine needs to be replaced. Which is not only time consuming, but costly.
In one detailed instance from the lawsuit, a plaintiff had to pay over $6,500 for repairs after Mazda refused to cover the costs. This despite the vehicle’s relatively low mileage, and the defect’s clear ties to manufacturing issues.
Moreover, the defect leads to increased environmental harm due to the potential for coolant leaks. These leaks can lead to harmful chemicals entering the environment, further adding to the defect’s negative impact.
Mazda’s Response and Recall Ineffectiveness
Despite issuing multiple Technical Service Bulletins (TSB) and acknowledging the need for design changes in parts such as the exhaust manifold gasket and the cylinder head, Mazda has not issued a recall that fully addresses the issue.
In fact, Mazda’s knowledge of the Engine Coolant Defect is apparent in TSBs, SAs, and SSMs as early as July 2020.
However, the TSBs issued by Mazda outline the defect and suggest repairs, yet fall short of offering a permanent solution. Making matters worst, Mazda denied covering all costs for affected vehicle owners.
The result–owners are left to deal with the financial burden themselves, as the repairs often fall outside of Mazda’s powertrain warranty coverage.
Owners Voices
2 weeks ago I noticed an oil leak 2019 cx5 . Riley Mazda of Stamford check and found a cracked on the cylinder head. The cylinder head needs to be replaced cost around $5000. luckily we noticed the leak while car was park. Imagine if the car was on the road. Dangerous things could have happened. Mazda is aware of this situation years ago. A technician Service Bulletin was released by Mazda in 2019/2021 to all dealerships technicians repair guideline and why the cylinder cracks. On the Mazda bulletin it clearly explained a design defect resulting cylinder head cracks. Also Mazda failed to warn cx5 owners about the dangerous situation. On top of everything Mazda refuse to pay the Defect cracked cylinder head that cost around $5000 . I email mazda Numerous times and decline any goodwill repair . Reason is out of warranty. Most Cylinder heads past 200,000 mile mark. Not unless your engine overheats but it not. Mazda should reimburse us owner who paid the repair cost
NHTSA Complaint Number: 11537823
Known issue in these CX-9’s. Had the issue fixed once with a brand new, Mazda, “redesigned engine.” 14 months and 30000 miles later it’s happening again. Leaking coolant due to cracked cylinder head. First repair was about 9 grand. This time my repair estimate since it’s premature was for another 6000 to replace the cylinder head versus the whole engine. That’s 15k on a used car when I could’ve almost paid it off with that amount at this point.
NHTSA Complaint Number: 11537823
Mazda has an open TSB Technical Service Bulletin for this and many other Mazda’s with the same engine- TSB-Collant Leaks at Cylinder Heads, Bulletin # – 01-013/21 issued 10/15/21 (CRACKED CYLINDER HEADS) My 2019 Mazda is right here on the list: Mazda Dealer claims I have to replace the engine at a cost estimated at $12,000 us dollars no offer or solution to repair the cylinder head which is upward of $5,000.00 us dollars. cars under there warranty are covered. Many models across the country are leaving people like myself stuck with a major engine issue and Mazda admitting they have a problem without stepping up and supporting and paying for this high repair cost to correct the issue. Enclosed is a snip of the actual TSB Mazda sent to all their Dealers. I’ve researched this Mazda engine and there’s cars out there with any where from 25k miles – 100k+ miles with this same issue Should be a Class Action Lawsuit. recall and Mazda needs to be honest with this most sensitive matter APPLICABLE MODEL(S)/VINS US Spec.: 2019-2020 CX-5 SKYACTIV-G 2.5T vehicles with VINs lower than JM3KF830243 (produced before Jun. 9, 2020) 2016-2020 CX-9 SKYACTIV-G 2.5T vehicles with VINs lower than JM3TC422801 (produced before Jun. 9, 2020) 2018-2020 Mazda6 SKYACTIV-G 2.5T vehicles with VINs lower than JM1GL523967 (produced before Mar. 25, 2020) Same engine has a class action lawsuit against Mazda for burring engine oil they both tie together.
NHTSA Complaint Number: 11564776
Mazda Models Affected
The following models are affected by the coolant defect.
- 2019 Mazda CX-5
- 2020 Mazda CX-5
- 2016 Mazda CX-9
- 2017 Mazda CX-9
- 2018 Mazda CX-9
- 2019 Mazda CX-9
- 2020 Mazda CX-9
- 2018 Mazda6
- 2019 Mazda6
- 2020 Mazda6
Status of the Mazda SKYACTIV-G 2.5T Cooling Defect Class Action Litigation
Jarvis et al. v. Mazda Motor of America, Inc., et al., Case No. 3:24-cv-02159-RFL, in the U.S. District Court for the Northern District of California. This is an active lawsuit.
Filed by the law firms of: Nye, Stirling, Hale, Miller & Sweet LLP and Sauder Schelkopf LLC.
Questions About This Lawsuit?
MyCarVoice.com is not counsel or the settlement administrator in this class action lawsuit. Our goal is to inform owners of these vehicles of the recent lawsuit. However, this post will be updated when/if new suit information is released.
Please considering subscribing to this post for critical updates.
Are you driving a Mazda CX-5, CX-9, or Mazda6 and experienced problems with the coolant system? If so, add your voice to this post in the comments below, or over at the MyCarVoice Mazda Community page.
Final Thoughts: The Ongoing Battle for Accountability
The class action lawsuit represents a critical step toward accountability, aiming to compensate affected owners and ensure that Mazda addresses the engine coolant defect.
For owners of Mazda vehicles with the SKYACTIV-G 2.5T engine, staying informed about the progress of this lawsuit is vital. The outcome could not only influence the financial and safety aspects of owning an affected vehicle, but also set a precedent for how automotive manufacturers handle defects affecting vehicle safety and integrity.
As the legal battle unfolds, the message is clear: manufacturers must prioritize transparency and swift action when it comes to defects that compromise both the performance and safety of their vehicles.
Are you driving a Mazda and experienced an engine cooling defect with the SKYACTIV-G 2.5T engine? If so, add your voice to this post in the comments below.
Managing Editor
Christopher is an automotive technical writer. When he’s not at the local autocross event, he can often be found working on one of his cars. Specializes in automotive class action law, industry trends, and automotive maintenance. Email me direct, or learn more about us
Aidar
March 13, 2025 at 12:48 amMazda CX-9 2017, mileage 119,924.64 miles
I also had a cracked cylinder head a month ago.
I emailed Mazda headquarters (Tsdcustomer@mail.mazda.co.jp), hopefully this emai is a working one. I think we need to give this issue more media publicity!
After reading the comments, I realized that many people have this problem on skyactive 2.5G Turbo
Jackie Lynn Cleveland
March 3, 2025 at 7:20 pmI have received a notice from Mazda in December 2024 stating that my “Mazda” 2017 CX-9 skyactiv-G 2.5T engine may have “coolant leak problems at the cylinder head around the exhaust manifold” they are “extending the limited powertrain warranty to 10 years or 120,00 miles, whichever comes first”. (supposedly they are covering the cost of repairs) Just 1 week ago I have began smelling the coolant burn scent, and have seen evidence of a few small drops of coolant on garage floor after driving my car. My car only has 64,182 easy miles on it! SO FOR ANYONE HAVING THIS ISSUE….. The notice states that Mazda 2019-2020 CX-5, 2016-202 CX-9 or 2018-2020 Mazda6 vehicles with Skyactiv-G 2.5T engines are covered. BUT stipulates that the vehicle must be examined by the Mazda Dealership for the diagnosis of “Service bulletin 01-002/23” before they will honor the extended warranty. Clearly they know they have a big problem with this engine!! The vehicle sold for 44,000.00 brand new just 7 years ago. My question is, can I drive it the 65 miles to the dealership without causing more harm to the engine or should it be towed? It has not overheated and I do not have any check engine lights off any kind lighting up.
Christopher Rossen
March 4, 2025 at 4:01 pmHi Jackie I would reach out to the dealership and ask them about this.
Heidi
February 18, 2025 at 11:40 pmMy 2021 CX9 also had the same issue, cracked cylinder head caused by coolant leaking, only 31000 miles driven. Luckily it was still under the 5 year powertrain warranty so Mazda replaced the cylinder head for me.
Jenn Apps
November 20, 2024 at 11:51 pm2017 cx9 blew a head gasket from over heating and had to pay over $8000 for the repair. How do we go about holding Mazda accountable for this?
Tammy
November 20, 2024 at 9:42 amYup, 2016 cx9. Coolant leak found in 2024
At 110k. Researching
Ronnie Reyes
October 6, 2024 at 5:38 amrecently bought a sed 2019 cx9 FWD with 80k kms here in the Philippines. haven’t experienced anything wrong so far but am deeply concerned about the potential fir a catastrophic engine failure.
inquired about it with a local dealership but they professed lack of knowledge about the issue.
will appreciate any advice as to how owners outside of the US can get some relief from this issue too. thanks
Leah Scott
September 26, 2024 at 7:14 pmAdd me to this unfortunate list of affected people. I have loved my 2018 CX9 since I bought it, paid it off early since I retired and didnt want a car payment on a fixed income. I maintain my car diligently and know every sound and smell, so i take it in immediately when anything is off. It has never overheated, been low on coolant levels, smelled of burning anti freeze or had any drips of it underneath. only ongoing issue has been a mystery freon leak, which was remedied finally. I took it back in because the ac was only blowing cool (not cold) and wanted to be sure it wasnt still leaking. When they removed the engine cover underneath, the engine was caked with baked on coolant. It was 1.5 gallons low, which he topped off. my oil had been changed a month or two prior and the fluids were all good at that time. I googled this and found a huge (known) issue which is widespread and known by mazda. I took it directly to a mazda dealer and it needs an entire new engine ($10k) which are on back order, or a rebuilt engine ($7k) which can be done sooner. Both are unacceptable for a car that is only 6 years old and impeccably maintained. The TSBs that they have published acknowledge on page 2, that this is their own fault during manufacturing. They have made no effort to let owners know of this issue (which is not preventible anyway, it requires a partial engine replacement at the very least, as their ‘solution’). I paid $30k for my car, and am not about to spend another $10k on top of that for an engine that mazda should have installed in the first place. This is their fault, they knowingly sold these defective engines and said nothing to the vehicle owners even after this was discovered.
Chris
September 5, 2024 at 7:57 amThis must be a PR and potential financial nightmare for Mazda. Their marketing department must be (sky) active.
Short of a recall involving an install of a new engine, I don’t see how this can be adequately addressed and remedied. This is a major safety issue if the car especially if the car fails in heavy traffic, craps out in the middle of nowhere, car is full of a family/kids, etc…Yikes!
This a text book product defect case, especially if the root of the cause is metal fatigue. I hope the class action attorneys take this all the way and demand an engine replacement. It was built with defective materials, plain and simple. Discovery into Mazda’s records will be revealing for sure.
Shame on Mazda for not being proactive on this and worse yet hiding behind the warranty’s expiration in denying claims.
Cheryl Daniels-James
September 17, 2024 at 10:11 pmI just had this issue happen to my beautiful 2018 CX9. I can’t drive my car and it’s waiting for an appointment at the dealership later this month. I still owe over $10k on it and now I have no vehicle. 🙁
Mazda MUST make this right.
Dan
September 2, 2024 at 9:09 amMake sure to change your OEM oil as recommended in owner manual or sooner!
Debbie Bastis
August 27, 2024 at 5:06 pmThis is exactly what happened to my 2016 CX5 four months after purchasing it in 2020. It had 72,000 miles when I purchased it. The mechanic couldn’t explain how coolant got in the engine. But he had another customer with the same problem within a year or two later.
Autumn P
August 14, 2024 at 2:24 pmMy 2017 CX-9 presented the coolant leak problem in January of 2022 at roughly 65K miles. I am very interested to see how this pans out.
matthew keen
August 12, 2024 at 4:00 pmsame issue. CX-9 with 68,000 km. bought last year because of low mileage. shop still diagnosing but they think maybe just the turbo cooling hose. I’m in Canada so hoping this action will cover here as well
Ji Lee
August 8, 2024 at 11:40 amFound major coolant leakage issue on my 2018 Mazda 6 Signature with 55k miles.
Local Mazda service diagnosed with cylinder head warpage causing the coolant leak. Powertrain warranty expired Aug 2023 and fix service quote came out to $13k.
Called Mazda US and opened a case#, which they say the case manager will call back in 72 hours.
Christopher Rossen
August 8, 2024 at 12:25 pmKeep me posted on this.
Mike S
August 2, 2024 at 6:48 pmI have a 2017 CX-9 Signature and experienced the first signs of the coolant leak at 96k miles. The car red thermostat started flashing on the dashboard and I pulled over immediately. Classic Mazda in Orlando has confirmed the leak is due to the known issue, Technical Service Bulletin TSB 01-002/23. They’ve quoted me over $7500 to get it fixed and said it’s on me. I’ve been a two car Mazda owner for the last 10 years. I expect these cars to last at least to 200k miles or longer. Time to change brands. I’m going to start a barrage of formal complaints and see where it gets me. Otherwise, no more Mazda.
Ray
June 12, 2024 at 1:58 amI’ve recently got my 2.5T engine replaced in my 2018 Mazda6 for a cracked cylinder head. My car had 59k miles and passed the warranty coverage by a couple of weeks. I paid $3,500 for this fix and fear this problem is not completely over yet. I didn’t understand how the engine can suffer such a fate since I’ve kept up my routine maintenance. The service Advisors claimed that they were not aware of any issues with this engine. That is until I found this page and the accompanying video. I had no idea about the design flaw… which makes sense. I’m still pretty annoyed about having to replace the engine.
Francisco Javier Ambriz Rivera
May 28, 2024 at 2:35 pmOne more joining the club!!! This past Memorial Day weekend, I had to help my son to tow back from Taos, NM to El Paso, Tx, his 2016 Mazda CX9. Yeup!! You guessed it right!! Vehicle overheated and apparently engine is done.
Claude
April 27, 2024 at 10:51 amYes, my vehicle is on the “trouble list”. No problem yet. 2019 cx5. Only 30,000 milles. I am in Canada, so I hope this suit also includes Canadian cars. My warranty expires soon. May12-2024. The last thing I need is a $10,000 repair bill. And I would feel bad selling the car, leaving the new owner with the upcoming problem. Also, the taxes on a new car (13% in Canada) would eat up half the cost of the repair. No win situation.