NHTSA Complaint #11633877 — 2018 MAZDA CX-5

At approximately 65,000 miles, a burning oil odor was detected, and we took our vehicle to the nearest Mazda dealership. Techs confirmed a failed master cylinder resulting in a leak, and that this master cylinder failure is common with 2018 CX-5s resulting from porosity in the cast metal wall creating a leak path over time. I was able to retain the failed casting and all parts which were replaced and am saving for records and analysis. Mazda customer service was contacted about the master cylinder casting failure and declined to cover it because the vehicle was beyond warranty period and because the failure was repaired before I was able to establish contact with Mazda customer service. Note that the failure happened in the approach to the holidays, and while efforts were made to establish contact with Mazda service via website chat, e-mail form submission, and phone, they were unsuccessful due to technical issues on the Mazda site and a non-responsive phone line. I can confirm that my local dealership POC provided me with Mazda corporate contact info per my request when the diagnosis was made (e-mail copies available.) The issue was not on my end, as efforts were made again immediately after Christmas, and phone and website chat were immediately successful when attempted. The website chat log indicating their denial and rationale for denial is available. This same vehicle has also had an issue with the front timing cover leaking as several others have noted, and this issue was also acknowledged by local dealership technicians as an endemic issue with this model. The front timing cover issue were identified and repaired within the 60,000-mile warranty. Copies of available correspondence with Mazda, including dealer invoices/receipts, service records for the vehicle (all done at Mazda dealerships) and chat history with Mazda customer service can be provided.