2018 Mazda 6 — MOT failures & pass rate
Across 18,016 MOT tests analysed for the 2018 Mazda 6, the most common recorded failure areas were tyres, brakes and visibility. Its pass rate of 90.2% was above the average for large family cars of a similar age (87.5%). Higher-mileage examples failed more often — 18.1% in the 150k+ group versus 5.5% in the 0-30k group.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 3.9% | 709 |
| 2 | Brakes | 3.1% | 554 |
| 3 | Visibility | 3.0% | 548 |
| 4 | Lighting & signalling | 2.0% | 360 |
| 5 | Suspension | 1.8% | 315 |
| 6 | Emissions & environmental | 0.6% | 108 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Wipers | 510 |
| 2 | Brake pads | 498 |
| 3 | Tread depth | 305 |
| 4 | Headlamp aim | 275 |
| 5 | Washers | 146 |
| 6 | Coil spring | 146 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 23.6% | 4,250 |
| 2 | Brakes | 21.0% | 3,789 |
| 3 | Other defects | 6.4% | 1,145 |
| 4 | Visibility | 3.5% | 635 |
| 5 | Suspension | 3.3% | 585 |
| 6 | Road wheels | 0.9% | 157 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 5,452 | 5.5% |
| 30-60k | 7,789 | 10.6% |
| 60-90k | 3,354 | 12.6% |
| 90-120k | 1,042 | 14.7% |
| 120-150k | 284 | 15.1% |
| 150k+ | 94 | 18.1% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 9,474 | 8.7% |
| Diesel | 8,542 | 10.9% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 3,553 | 6.1% |
| 2022 | 3,563 | 7.8% |
| 2023 | 3,624 | 10.0% |
| 2024 | 3,618 | 11.6% |
| 2025 | 3,658 | 13.2% |
What to check before buying a 2018 6
Before buying a 2018 Mazda 6, focus on the areas it most often fails on. Tyres accounted for 3.9% of tests for this year.
- Tyres (3.9% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
- Brakes (3.1% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
- Visibility (3.0% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£150.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How many 2018 Mazda 6s pass their MOT?
90.2% of the 18,016 2018 Mazda 6 MOT tests in this dataset passed — a 9.8% fail rate.
What is the most common MOT failure on a 2018 Mazda 6?
Tyres, recorded in 3.9% of tests, followed by brakes (3.1%).
Does the 2018 6 get worse with mileage?
Its MOT fail rate rises from 5.5% in the 0-30k band to 18.1% in the 150k+ band.
Methodology & source. Based on 18,016 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.