2018 BMW M3 — MOT failures & pass rate
4,751 MOT tests on the 2018 BMW M3 are in this dataset, and 91.5% of them passed. Executive cars of a similar age fail 10.8% of the time, so this is 2.3pp better than the group it competes with. Failures cluster in tyres, suspension and lighting & signalling.
What the MOT record shows
Tyres dominates the failure mix at 5.7% of all tests — 4.2 points clear of suspension, so it is the first thing to check.
At component level the recurring items are registration plates, coil spring and headlamp aim — registration plates alone was recorded 82 times.
Mileage is the strongest signal on the record: 7.1% of 0-30k cars fail, rising to 11.3% once past 60-90k.
Advisories point at the next bill rather than this one: tyres was flagged on 11.3% of tests without failing them.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 5.7% | 269 |
| 2 | Suspension | 1.5% | 71 |
| 3 | Lighting & signalling | 1.1% | 52 |
| 4 | Other defects | 1.0% | 49 |
| 5 | Visibility | 0.5% | 23 |
| 6 | Emissions & environmental | 0.4% | 21 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Registration plates | 82 |
| 2 | Coil spring | 52 |
| 3 | Headlamp aim | 49 |
| 4 | Tread depth | 42 |
| 5 | Catalyst emissions | 26 |
| 6 | Ball joint | 24 |
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 | 11.3% | 538 |
| 2 | Other defects | 4.6% | 219 |
| 3 | Brakes | 3.5% | 165 |
| 4 | Visibility | 2.5% | 120 |
| 5 | Suspension | 1.0% | 46 |
| 6 | Emissions & environmental | 0.5% | 24 |
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 | 2,451 | 7.1% |
| 30-60k | 2,018 | 9.7% |
| 60-90k | 257 | 11.3% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 1,077 | 9.3% |
| 2022 | 988 | 7.3% |
| 2023 | 948 | 8.3% |
| 2024 | 855 | 7.5% |
| 2025 | 883 | 9.8% |
What to check before buying a 2018 M3
On a 2018 M3, tyres is what the MOT record says goes wrong most — it appeared in 5.7% of tests. Check these areas before you commit.
- Tyres (5.7% 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.
- Suspension (1.5% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
- Lighting & signalling (1.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£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 BMW M3s pass their MOT?
91.5% of the 4,751 2018 BMW M3 MOT tests in this dataset passed — a 8.5% fail rate.
What is the most common MOT failure on a 2018 BMW M3?
Tyres, recorded in 5.7% of tests, followed by suspension (1.5%).
Does the 2018 M3 get worse with mileage?
Its MOT fail rate rises from 7.1% in the 0-30k band to 11.3% in the 60-90k band.
Methodology & source. Based on 4,751 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.