Mazda Coolant Leak Lawsuit Investigation for the CX5, CX9 and Mazda6

Attorneys working with ClassAction.org are investigating whether a defect is causing coolant leaks in certain Mazda CX-5, CX-9 and Mazda6 vehicles and, if so, whether a class action lawsuit can be filed.

Numerous complaints have been posted online about leaking coolant in the cars, with some drivers saying they had to pay for costly repairs, including engine replacement, and expressing concerns about vehicle safety.

Attorneys suspect Mazda knows about the problem – even going so far as to send a special alert to vehicle technicians – but is refusing to recall the cars or offer a free fix.  

It’s possible that a class action lawsuit could be filed to help affected owners and lessees, but attorneys first need to speak with those who’ve experienced the Mazda coolant leak issue.

Has There Been a Mazda Coolant Leak Recall?

There has not been a recall over the Mazda coolant problems; however, in June 2022, the automaker issued an updated technical service bulletin, a communication from a car manufacturer to service centers that describes a common problem with a particular model and offers advice on how to fix it. 

According to the bulletin, 2019-2020 CX-5, 2016-2020 CX-9 and 2018-2020 Mazda6 Skyactiv-G 2.5T vehicles with certain VIN numbers could experience coolant leaks. The location of the Mazda coolant leak is at the cylinder head around the exhaust manifold, the company’s notice says. Specifically, the bulletin states that cracks could develop at the stud bolt hole or at the outside of the exhaust manifold and identified the following as possible causes:

“Deformation of the exhaust manifold during usage causing unexpected force to certain areas of the cylinder head.

Residual stress generated during production in the cylinder head material may be greater than expected. The external force from the exhaust system when driving over bumps may cause unexpected force to certain areas of the cylinder head.”

While auto recalls often come with free fixes, cars exhibiting problems described in technical service bulletins generally do not have their repair costs covered if there is no applicable warranty. A class action lawsuit could help Mazda drivers recover the money they’ve spent fixing the coolant leak issue. 

CX-5, CX-9 and Mazda6 Leaking Coolant: Drivers Complain on Reddit, Forums

Mazda drivers have taken to the internet to express concerns about the coolant leak issue, sending complaints to the National Highway Traffic Safety Administration (NHTSA) and posting to Reddit and other web forums. Below is a sampling of some online complaints [sic throughout, emphasis ours]: 

So found out the hard way that a coolant leak means you have a cracked cylinder head. I brought my car to the dealership and they confirmed this. He also said they pulled a code that the engine overheated and now I need an entire engine replacement.”
— 2016 Mazda CX9 driver, Reddit.com

Coolant leaking from head, informed by dealer the cylinder head is cracked and the entire engine needs to be replaced. The engine has just hit 80k miles at this point. This issue caused multiple instances of overheating while driving, one of which caused the vehicle to fail to move forward while on an elevated freeway overpass with no shoulder during rush hour. This issue appears to be widespread for 2016 and newer Mazda models with the 2.5L turbo engine.”
— 2018 Mazda6 driver, NHTSA ID number 11548064

I owned mazda cx5 2019, it has been my favorite car in term of driving and handling. But, the reliability is very questionable. I had to bring my car to dealership to fix 3 times regarding the coolant leak issue. Now guess what, my warranty ran out after 36k and my car is only at 40k. I am really not seeing myself getting Mazda in the future.”
— 2019 Mazda CX-5 driver, Reddit.com

Driving on a major highway, when the engine overheating temperature light appeared on the instrument cluster. Seconds later it appeared and felt as if the engine would seize and come to an abrupt halt in the middle of a major highway. Thankfully I was able to quickly find a place with room to pull over, avoiding a potential collision. The engine coolant abruptly leaked/exited from the vehicle. I believe there is a service bulletin (no. - 01-002/23), but still no signs of a recall being issued in reference to this safety concern.”
— 2018 Mazda CX9 driver, CarProblemZoo.com

I experienced coolant leaking from the cylinder head. Mazda is quoting me over $7700 for the repairs. There was a TSB released, there had been numerous revised versions the same issue, in Feb 2023 finally including my vehicle. Mazda knowingly put me and my family’s safety in jeopardy by not including me sooner, and now have left me with an astronomical repair bill for an issue they’ve known has existed for years. Had they alerted me when the originally discovered the issue, the vehicle would’ve been under warranty and they would’ve had to replace the parts under warranty.”
— 2017 Mazda CX9 driver, CarProblemZoo.com

Mazda Coolant Leak Symptoms  

One 2018 CX-9 driver who experienced the Mazda coolant leak issue described the smell as “syrupy” and said he noticed dark green residue “all over” the oil filter and surrounding components.

How Could a Mazda Coolant Leak Lawsuit Help?

A Mazda coolant leak lawsuit could help drivers recover money for repair costs, engine damage and loss of vehicle value. It could also force the automaker to provide a free fix or extend warranties for vehicles that have yet to exhibit the issue. 

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