This bulletin supersedes the previously issued bulletin(s) listed below. The changes are noted in Red. 01-008/23 06/05/23 Some vehicles may exhibit rattling noises from the engine compartment and oil leakage from the drive belt auto tensioner. This may be caused by insufficient sealing at the drive belt auto tensioner damper when the auto tensioner fully operates under both high ambient temperature and high load conditions. To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed. REPAIR PROCEDURE If the tensioner is found to be "No Good" after completing the Drive Belt Auto Tensioner Inspection, replace it with a modified part according to the instructio
full bulletin at NHTSA ↗2018 Mazda Mazda3 powertrain problems
moderate Owners of the 2018 Mazda Mazda3 have filed 5 NHTSA complaints about the powertrain at roughly $2,500 to repair (U.S. federal records, as of August 2026). Source: NHTSA Office of Defects Investigation. See powertrain across all vehicles →
| Model year | powertrain complaints |
|---|---|
| 2014 Mazda3 | 7 |
| 2015 Mazda3 | 5 |
| 2016 Mazda3 | 9 |
| 2017 Mazda3 | 3 |
| 2018 Mazda3 (this page) | 5 |
| 2019 Mazda3 | 9 |
| 2021 Mazda3 | 3 |
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering powertrain on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
This Service Alert supersedes the previously issued SA listed below: The changes are noted in Red. SA-011/24 02/12/24, 06/06/24, 07/29/24 DESCRIPTION Mazda has developed factory recommended scheduled maintenance services that support all major vehicle systems. Mazda recommends dealers follow the scheduled maintenance tables as cited in the vehicle-specific workshop manual or owner's manual. Services performed outside of Mazda's factory scheduled maintenance are not recommended. These services are unnecessary and create unneeded expenses for your customers. SCHEDULED MAINTENANCE Refer to the applicable Workshop Manual or Owner's Manual for vehicle -specific manufacturer scheduled maintenance.
full bulletin at NHTSA ↗Noise, Vibration, and Harshness (NVH) Diagnostic Guidelines Diagnostic Guidelines When diagnosing NVH concerns, it is essential to first classify the issue into one of three primary categories: Noise, Vibration, or Harshness. Many customer complaints may involve overlapping symptoms, such as both noise and vibration, so identifying the dominant characteristic is critical. Once the primary symptom is determined, follow the appropriate diagnostic path. For example, if a concern includes both noise and vibration but is related to vehicle speed, the vibration diagnostic path should be followed. When considering component replacement during the diagnostic process, it is best practice to start wit
full bulletin at NHTSA ↗Some customer's might state that they notice fluid or oil leaking/dripping on the ground when the vehicle is parked. For this concern, inspect the vehicle for any trace of a fluid or oil leak and use the following examples as a guide to determine if it is severe enough to require a repair, or just to clean the area and monitor it at the next service. Examples of residue or seepage that may not be considered a leak and that may not require repair based on splash shield inspection.
full bulletin at NHTSA ↗The SKYACTIV-DRIVE FW6A-EL AT uses “Automatic Transmission Fluid (ATF) Type: FZ”. Only use “ATF-FZ” to fill or top off the fluid level. ATF-FZ is specially designed for use in the SKYACTIV-DRIVE series AT. It is a low viscosity formula with less friction for better fuel economy. NOTE: ATF-FZ is colored blue for easy identification.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 2 most recent
My 2018 Mazda 3 has an intermittent electrical failure on the high-speed CAN network that causes multiple safety-critical systems to fail while driving. When the fault occurs, the dash lights up with warnings for powertrain, ABS/traction, lane departure, collision-avoidance, TPMS, immobilizer, and the check-engine light. The car also hesitates or “lurches” between 15–30 mph during these events.…
What component or system failed or malfunctioned, and is it available for inspection upon request? The high-pressure fuel pump failed. This component failure prevents the car from starting or staying running. The check engine code confirmed the high-pressure fuel pump failure. The failed component is currently at the Mazda dealership and is available for inspection upon request. How was your…
Common questions
How serious is the powertrain problem on the 2018 Mazda Mazda3?
It's a documented issue but not catastrophic. 5 complaints have been filed. Repairs average $2,500 and most owners catch it before it causes a breakdown.
At what mileage does the powertrain typically fail?
Based on the 5 complaints filed, powertrain issues most often appear around 32,000 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $2,500 for powertrain repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to powertrain?
No active recalls currently cover powertrain issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.