2014 Mercedes-Benz Gl — MOT failures & pass rate
The 2014 Mercedes-Benz Gl passed 87.8% of its 3,026 recorded MOT tests. Against large SUVs of a similar age (15.0% fail rate), the 2014 Gl comes out 2.9pp better. Failures cluster in tyres, lighting & signalling and emissions & environmental.
What the MOT record shows
No single area dominates — tyres (5.9%) and lighting & signalling (4.1%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are tread depth, malfunction indicator lamp and headlamp aim — tread depth alone was recorded 124 times.
Mileage matters less than usual here: the 2014 Gl fails 6.5% of the time in the 0-30k band and 9.5% at 150k+, a spread of only 3.1 points.
Tyres is the most common advisory, noted on 22.9% of tests — work that passed today but is likely due soon.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 5.9% | 178 |
| 2 | Lighting & signalling | 4.1% | 124 |
| 3 | Emissions & environmental | 2.9% | 88 |
| 4 | Brakes | 1.8% | 55 |
| 5 | Body, structure & corrosion | 1.6% | 49 |
| 6 | Visibility | 1.5% | 46 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Tread depth | 124 |
| 2 | Malfunction indicator lamp | 84 |
| 3 | Headlamp aim | 61 |
| 4 | Joints | 49 |
| 5 | Brake pads | 39 |
| 6 | Stop lamp | 37 |
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 | 22.9% | 694 |
| 2 | Brakes | 14.7% | 445 |
| 3 | Other defects | 7.4% | 225 |
| 4 | Body, structure & corrosion | 5.0% | 152 |
| 5 | Suspension | 4.1% | 125 |
| 6 | Visibility | 3.8% | 114 |
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 | 93 | 6.5% |
| 30-60k | 697 | 12.8% |
| 60-90k | 1,177 | 12.5% |
| 90-120k | 752 | 12.4% |
| 120-150k | 223 | 11.2% |
| 150k+ | 84 | 9.5% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 2,555 | 13.0% |
| Petrol | 471 | 7.9% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 623 | 11.4% |
| 2022 | 619 | 13.3% |
| 2023 | 606 | 12.7% |
| 2024 | 596 | 12.1% |
| 2025 | 582 | 11.3% |
What to check before buying a 2014 Gl
The failure pattern for this year is specific enough to inspect against: tyres accounted for 5.9% of tests. Start there.
- Tyres (5.9% 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.
- Lighting & signalling (4.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Emissions & environmental (2.9% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
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 2014 Mercedes-Benz Gls pass their MOT?
87.8% of the 3,026 2014 Mercedes-Benz Gl MOT tests in this dataset passed — a 12.2% fail rate.
What is the most common MOT failure on a 2014 Mercedes-Benz Gl?
Tyres, recorded in 5.9% of tests, followed by lighting & signalling (4.1%).
Does the 2014 Gl get worse with mileage?
Its MOT fail rate rises from 6.5% in the 0-30k band to 9.5% in the 150k+ band.
Methodology & source. Based on 3,026 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.