There are 2 stored owner reports matching the powertrain & transmission leading-label group for the 2017 Mazda CX-9 in our NHTSA-sourced dataset. These are unverified consumer reports and may not reflect confirmed defects.
This group counts stored reports whose component label starts with one of this site's matching prefixes, ignoring case. Each matching report counts once within the group. Components mentioned later in the label or only in the narrative are not searched. How component counts work
Loaded 2 of 2 matching reports.
Open the full vehicle complaint log (all categories)Coolant leak cylinder head. It was running and i could smell coolant on the minifalda and it shout down.
There was a coolant leak on my Mazda CX9 Signature with a 2.5T engine, and when driving the engine temperature started increasing slightly before taking off and turning red. I had to pull off to the side of a busy interstate road very quickly and shut the vehicle down before it overheated any more. Once I got the vehicle to the dealership, they told me it was a cracked cylinder head leaking coolant, and that it was an extremely common problem for the 2.5T mazda engines around about 60k miles, and they were actively working on one in the shop where I was for the same problem. Mazda is not currently helping with engine swap or any repairs as a result and is sticking the customer with the bill.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
NHTSA source checks for this vehicle year
Checks are recorded separately for each dataset, not for the whole page. Dates use UTC. A missing check date does not mean no records exist.
Vehicle import recorded: Apr 28, 2026. This is the stored import date, not confirmation that every source was successfully refreshed.