3 complaints reported

2018 Mazda Mazda6 POWER TRAIN,ENGINE

Owner-reported problems and safety issues filed with NHTSA. Review common failures, severity levels, and complaint trends over time.

Reports
3
Crashes
0
Fires
0
Injuries
0

Complaint Timeline

Chronological view of owner reports

Jul 2026

I recently discovered a significant oil leak near the exhaust manifold of my 2018 Mazda 6 (2.5L NA), which has resulted in visible smoke and a burning oil odor. Upon taking the vehicle to the nearest Mazda dealership for a diagnosis, the service department informed me that the vehicle has suffered a cracked cylinder head. An active oil drip is visible behind the engine near the exhaust manifold immediately upon starting the car; consequently, the engine is leaking oil directly onto the exhaust components. This condition not only renders the vehicle inoperable but also presents a significant safety and fire hazard. At the time of this writing, my vehicle has only 46,996 miles and has been meticulously maintained. This mileage is well under the 60,000-mile powertrain threshold and represents a premature failure of a major internal engine component. There are numerous reports on Mazda owner forums describing this identical issue occurring in Mazda 6, CX-5, and CX-9 models. Some owners have even reported instances of minor fires or active burning under the hood due to oil contacting hot engine components. Mazda released Technical Service Bulletin TSB #MC-10241612-0001 (SA-037-23), which includes a redesigned cylinder head for 2018–2020 Mazda 6, 2019 CX-5, and 2016–2020 CX-9 models, demonstrating Mazda’s awareness of this design flaw. While the TSB currently only specifies the 2.5L Turbo engines and not the naturally aspirated variants, there is substantial evidence that this is a widespread defect across these model years, unrelated to owner misuse or vehicle mileage. Mazda should take full responsibility by issuing a formal recall or providing an extended warranty to cover naturally aspirated engines, thereby addressing this problem and preventing further safety risks.

Type: Vehicle, Vehicle: 2018 MAZDA MAZDA6, Manufacturer: Mazda Motor Corp.
Incident: Dec 2025
Mar 2024

Noticed slight coolant leak, took car to mechanic, he stated cylinder head was cracked, & causing coolant to spray everywhere. Towed car to dealer. Was given repair estimate of over $11,000, for a new engine. I see a safety bulletin online for my year make & model car. This overheating can apparently cause an engine fire. So far, Mazda seems to be showing negligence & not properly addressing the issue for owners.

Type: Vehicle, Vehicle: 2018 MAZDA MAZDA6, Manufacturer: Mazda Motor Corp.
Incident: Mar 2024
Aug 2019

VEHIXLE HAS OPEN RECALL #3719F. TOOK VEHICLE IN FOR SERVICE ON JULY 15 AND ACCORDING TO NHTSA RECALL HAS EVEN OUT SINCE JUNE 27.2019. TO THIS DAY I HAVE NOT GOTTEN ANY LETTER OR ANYTHING STATING CAR HAS OPEN RECALL WHEN THE CAR CAN TURN OF RANDOMLY. WILL BE TAKING CAR IN ON 08/26/19 BUT I'M CONCERNED AS TO WHY THIS HAS NOT BEEN ADDRESSED IN ANY LETTERS OR EMAILS

Type: Vehicle, Vehicle: 2018 MAZDA MAZDA6, Manufacturer: Mazda Motor Corp.
Incident: Aug 2019

Trend Over Time

Complaints by year

Quick Summary

The 2018 Mazda Mazda6 has 3 POWER TRAIN,ENGINE complaints on file. Review the timeline above for detailed owner experiences.