The Mazda CX-8, introduced in 2017, fills a unique role in Mazda’s SUV lineup, combining the spaciousness of the CX-9 with a narrower design, making it ideal for families who need three rows of seating but prefer a slightly smaller footprint. With its elegant design, refined interior, and powerful diesel and petrol engine options, the CX-8 is a popular choice among midsize SUV buyers. However, despite Mazda’s reputation for reliability, the CX-8 has a few known issues that are essential for prospective buyers to understand. This article provides a detailed overview of common problems, what to look for when buying a used CX-8, and the expected cost of ownership.
Common Problems with the 2017-Present Mazda CX-8
1. Diesel Particulate Filter (DPF) Issues in Diesel Models
The Mazda CX-8’s diesel models, especially those in urban environments or those that undertake short drives frequently, are susceptible to Diesel Particulate Filter (DPF) clogging. The DPF, a component designed to trap soot and reduce emissions, can clog if it doesn’t reach high enough temperatures to burn off accumulated particles, an issue common with frequent short drives or city driving. Clogging can lead to reduced engine performance, increased fuel consumption, and, in some cases, the engine entering "limp mode" as a protective measure.
Signs and Prevention: Drivers should look for dashboard warning lights related to the DPF and monitor performance changes, such as reduced power or unusual smoke from the exhaust. For buyers considering a diesel CX-8 but who mainly drive short distances, opting for a petrol variant may be more practical. For diesel owners, longer, steady-speed drives can help the DPF regenerate naturally, reducing the risk of blockages. In severe cases, a clogged DPF may require professional cleaning or replacement, both of which can be costly.
2. Automatic Transmission Hesitation
Some Mazda CX-8 owners report issues with the automatic transmission, particularly in diesel models. The transmission may hesitate or delay during shifts, creating a "lag" feeling between gear changes, especially when accelerating from low speeds. This issue can be caused by several factors, including software calibration issues or wear in the transmission components themselves. While this issue is not universal, it has been noted by enough owners to be worth considering, particularly for those who prioritize smooth, responsive shifting.
Signs and Prevention: During a test drive, pay attention to any hesitation or lag in the automatic transmission when accelerating from a standstill or during steady-speed driving. Mazda has provided software updates to address this issue, so verifying if these updates have been applied can be helpful. Regular transmission fluid changes as part of routine maintenance can also help prevent more severe transmission issues.
3. Excessive Engine Noise and Vibration
Diesel models of the CX-8, in particular, are known to produce more engine noise and vibrations, especially at lower speeds and during acceleration. While some degree of noise is expected in diesel engines, certain owners report it to be more noticeable in the CX-8 compared to competitors. Excessive engine noise and vibration can detract from the vehicle’s refined interior experience, especially on long trips.
Signs and Prevention: During a test drive, listen carefully to engine noise at both low and high speeds and assess whether it seems excessive. While regular maintenance can’t entirely eliminate engine noise in a diesel, well-maintained engines may reduce the extent of the issue. Prospective buyers who value a quieter cabin experience may prefer the petrol variant, which typically runs smoother and quieter.
4. Infotainment System Glitches and Freezing
The CX-8’s infotainment system, particularly in earlier models, may experience occasional glitches or freezing. Common complaints include slow response times, issues with Bluetooth connectivity, and random reboots. Mazda has addressed these issues in part through software updates, but some older models may still exhibit intermittent problems.
Signs and Prevention: During a test drive, thoroughly test the infotainment system by pairing a phone, navigating through various menus, and observing response times. If possible, verify with the seller or dealership if the latest software update has been applied, as this can improve the system's stability. In severe cases, replacement of the infotainment unit may be necessary.
5. Rear Suspension Wear and Noise
Some owners report wear in the rear suspension of the CX-8, particularly in high-mileage models. The rear suspension, which contributes to the SUV’s smooth ride and handling, may develop creaks, rattles, or knocks over time, especially when driven on rough or uneven surfaces. Rear suspension noise and wear can impact ride quality and, if left unaddressed, may lead to more extensive repairs.
Signs and Prevention: Listen for any unusual noises from the rear suspension while test-driving, especially on bumpy roads. Regular suspension inspections and maintenance can help catch early signs of wear, and worn components should be replaced to maintain optimal handling and comfort.
6. AdBlue Consumption and System Failures
Diesel models of the CX-8 use AdBlue, a urea-based additive that helps reduce emissions. Some owners report higher-than-expected AdBlue consumption, particularly in heavy traffic or city driving. In rare cases, owners have also experienced AdBlue system failures, which may require expensive repairs if they occur outside of warranty.
Signs and Prevention: Check the dashboard for any AdBlue-related warnings or faults. If considering a diesel model, make a note of the vehicle’s AdBlue consumption and inquire if the system has been serviced. If the CX-8 is still under warranty, addressing AdBlue system issues with a Mazda dealership can prevent future expenses.
7. Battery Drain in Petrol Models
Certain petrol models of the CX-8 have had issues with premature battery drain. Owners report that the battery may discharge quicker than expected, sometimes within just a few days of sitting idle. This problem can be due to a parasitic drain, where certain electronic components, such as the infotainment or anti-theft systems, continue to draw power even when the car is off.
Signs and Prevention: Test the battery’s performance and observe if the vehicle struggles to start, especially if it has been idle for a day or two. Prospective buyers should check the battery’s age and consider replacing it if it shows signs of wear. Regular use and disconnecting any unnecessary electronic accessories when parked for extended periods can also help prevent battery drain.
Buying Tips: What to Look for in a 2017-Present Mazda CX-8
Verify Recalls and Software Updates: Ensure that any recalls or software updates for issues like the infotainment system and transmission have been completed. Software updates are often available through Mazda dealerships and can improve overall performance.
Diesel vs. Petrol Decision: Diesel CX-8s are more fuel-efficient for long drives but come with risks like DPF clogging and higher AdBlue consumption. Petrol models may be preferable for those with primarily city driving needs or those who prefer a quieter ride.
Check for Suspension and Engine Noise: During a test drive, listen for any unusual sounds from the suspension or excessive engine noise, particularly with the diesel model. This can help reveal potential maintenance needs.
Examine Battery Condition: If considering a petrol model, ask about the battery’s age and check if it has been replaced. Batteries on some CX-8s may drain prematurely, leading to inconvenience and potential additional costs.
Cost of Ownership: Is the 2017-Present Mazda CX-8 Expensive to Own?
Fuel Economy
Diesel variants of the CX-8 typically provide better fuel efficiency, especially for long-distance travel, though petrol models are still competitive. Diesel drivers may see savings in fuel costs, but they should also budget for potential DPF maintenance or AdBlue costs, especially if the vehicle is used for short trips.
Maintenance and Repair Costs
While the Mazda CX-8 is generally reliable, diesel models may incur higher maintenance costs due to DPF cleaning, AdBlue system maintenance, and potential turbocharger issues. Petrol models have fewer emissions-related expenses but may experience battery drain and require more frequent maintenance of electronic components.
Insurance and Depreciation
Insurance costs for the CX-8 are moderate, falling within the average range for midsize SUVs. In terms of resale value, the CX-8 generally holds its value well due to Mazda’s reputation for reliability, but diesel models may depreciate slightly faster in regions where petrol vehicles are preferred.
Potential Extra Costs
Diesel CX-8 owners should budget for DPF maintenance and AdBlue refills, while those considering a petrol model may want to account for the potential need to replace the battery sooner than expected. Infotainment and electronic component repairs may also arise, especially in earlier models.
Conclusion
The 2017-Present Mazda CX-8 stands out as a versatile, family-friendly SUV with excellent build quality and a well-designed interior. However, prospective owners should be aware of a few common issues, particularly with diesel variants, including DPF clogging, transmission hesitations, and AdBlue consumption. By understanding these common problems and focusing on essential maintenance, buyers can make an informed decision and enjoy the benefits of the CX-8 with minimal unexpected costs.