2017 Mazda 6 diesel: common problems and MOT failures
What MOT testers find on the diesel Mazda 6 first registered in 2017 (diesel cars only): we looked at the 8,456 MOTs these cars had during 2023–2025. Plus known faults and what to look at before you buy one.
What goes wrong more than usual on a 2017 Mazda 6 diesel?
Parts flagged at MOT more often on the 2017 Mazda 6 diesel than on all cars registered in 2017.
- Rigid brake pipes4.3× usualMazda 64.3% All 2017 cars1%
Failed outright at MOT: 0.7%, against 0.1% of all 2017 cars. The rest were advisories or minor defects.
Rough price £100–£400 our estimateAt the viewing: Ask to see underneath, or check the MOT advisories: corroded brake or fuel pipes get worse every year and fail the MOT when they do.
- Suspension arm bushes and joints1.8× usualMazda 66.5% All 2017 cars3.7%
Failed outright at MOT: 0.3%, against 0.7% of all 2017 cars. The rest were advisories or minor defects.
Rough price £120–£180 (one arm) ClickMechanicAt the viewing: Listen for clunks over bumps and feel for the steering wandering. Worn arm bushes show as cracked rubber near the wheels.
- Wheels2.3× usualMazda 62.1% All 2017 cars0.9%
Failed outright at MOT: 0.4%, against 0.3% of all 2017 cars. The rest were advisories or minor defects.
Rough price £70–£150 our estimateAt the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.
- Ball joint1.9× usualMazda 62.6% All 2017 cars1.4%
Failed outright at MOT: 1.6%, against 0.7% of all 2017 cars. The rest were advisories or minor defects.
Rough price £60–£150 (one joint) ClickMechanicAt the viewing: Listen for knocking over bumps and check the rubber boots behind the wheels aren't split.
Common 2017 Mazda 6 diesel MOT failures and advisories
The share of 2017 Mazda 6 diesel MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.
- Tyres31% of testsRough price £70–£150
At the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.
- Brakes28% of testsRough price £150–£350
At the viewing: Look for a lip on the disc edges and feel for judder or pulling when braking firmly from about 40mph.
- Suspension17% of testsRough price £120–£400
At the viewing: Listen for knocks over speed bumps, and look behind each front wheel for a snapped coil spring.
- Lights and electrics8% of testsRough price £10–£80
At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.
- Wipers, windscreen and mirrors6% of testsRough price £15–£250
At the viewing: Check for chips in the driver's view, and test the wipers and washers.
- Seats and seatbelts3% of testsRough price £80–£250
At the viewing: Pull each seatbelt sharply. It should lock, and retract cleanly.
Known faults on the 2017 Mazda 6 diesel
Reported by owners, mechanics and buying guides for this model and age. Check which engine the car has, as some apply to one engine only.
- Diesel
Diesel in the oil (particulate filter)
If the engine is switched off during particulate filter cleaning, fuel can get into the oil and raise the level, which can damage the engine.
At the viewing: Check the oil isn’t above the max mark and ask what journeys it does.
- All engines
Airbag inflator and boot strut recalls
Driver’s airbag inflators can rupture after long exposure to humidity and must be replaced, and boot struts were recalled in 2017.
At the viewing: Ask a Mazda dealer to confirm the recalls were done.
- All engines
Warped brake discs
It can be hard on its brake discs, causing vibration under braking.
At the viewing: Brake firmly from speed and feel for shaking.
Questions to ask the seller before buying a 2017 Mazda 6 diesel
Ask before you travel to see it. A seller who knows the car will have answers, and receipts.
- Does it do regular motorway runs?
- Any recent work on the rigid brake pipes? (Flagged at MOT 4.3× as often on the 2017 Mazda 6 diesel as on other cars the same age.)
- Any recent work on the suspension arm bushes and joints? (Flagged at MOT 1.8× as often on the 2017 Mazda 6 diesel as on other cars the same age.)
- Any recent work on the wheels? (Flagged at MOT 2.3× as often on the 2017 Mazda 6 diesel as on other cars the same age.)
- Can I see the service history and receipts for any big jobs?
Looking at a Mazda 6?
Check the actual car: its own MOT history, mileage and what to ask the seller. Free, no sign-up.
Other years
Every year of the Mazda 6 compared
| Year | MOT tests | Most flagged |
|---|---|---|
| 2023 | – | Too new for MOT data |
| 2022 | 754 | Tyres 15% |
| 2021 | 1,288 | Tyres 22% |
| 2020 | 3,120 | Tyres 22% |
| 2019 | 13,161 | Tyres 26% |
| 2018 | 9,631 | Tyres 29% |
| 2016 | 20,504 | Brakes 29% |
| 2015 | 19,689 | Tyres 30% |
| 2014 | 18,402 | Suspension 34% |
| 2013 | 12,297 | Suspension 39% |
| 2012 | 8,508 | Brakes 41% |
| 2011 | 11,812 | Brakes 42% |
| 2010 | 15,127 | Brakes 44% |
| 2009 | 11,548 | Suspension 46% |
| 2008 | 10,079 | Suspension 48% |
| 2007 | 6,991 | Suspension 53% |
| 2006 | 4,017 | Suspension 50% |
| 2005 | 2,451 | Suspension 51% |
| 2004 | 1,127 | Suspension 52% |
| 2003 | 577 | Suspension 55% |
| 2002 | 228 | Suspension 53% |
Where this comes from: the DVSA's anonymised results for every MOT test done in Great Britain during 2023–2025, counting the MOTs of Mazda 6 cars first registered in 2017. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score