Mercedes-Benz S-Class MOT pass rate & common failures
Across 46 model years and 160,208 tests, the Mercedes-Benz S-Class passes its MOT 86.9% of the time. Executive cars of a similar age fail 16.8% of the time, so this is 3.7pp better than the group it competes with. Its most common failure areas are tyres, suspension and brakes.
Best and worst S-Class years
Ranked across S-Class years with at least 1,000 tests. Older cars fail more simply because they are older — compare years close together in age before drawing conclusions.
What the MOT record shows
Not every year is equal — 94.6% of 2022 examples pass against 78.2% of 2000 ones.
No single area dominates — tyres (4.6%) and suspension (4.4%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are ball joint, tread depth and headlamp aim — ball joint alone was recorded 5,092 times.
A 150k+ example is materially riskier than a 0-30k one: 17.0% versus 6.4%.
The hybrid cars hold up better: 7.8% fail against 14.0% for petrol, a 6.2-point gap across 49,508 tests.
Tyres is the most common advisory, noted on 20.3% of tests — work that passed today but is likely due soon.
The trend is improving — the fail rate fell from 14.3% in 2021 to 12.1% in 2025, as the worst-kept examples leave the fleet.
How it compares
Versions & engines
MOT records broken out by the engine designations buyers actually search for.
By model year
Every S-Class model year with a usable sample. Years with their own detailed report are linked.
| Year | Tests | Pass rate | Fail rate | Most common failure |
|---|---|---|---|---|
| 1983 | 33 | 87.9% | 12.1% | Suspension |
| 1984 | 105 | 84.8% | 15.2% | Lighting & signalling |
| 1985 | 120 | 80.8% | 19.2% | Lighting & signalling |
| 1986 | 122 | 82.8% | 17.2% | Lighting & signalling |
| 1987 | 157 | 82.8% | 17.2% | Lighting & signalling |
| 1988 | 171 | 84.8% | 15.2% | Lighting & signalling |
| 1989 | 267 | 85.4% | 14.6% | Suspension |
| 1990 | 271 | 83.0% | 17.0% | Lighting & signalling |
| 1991 | 254 | 86.6% | 13.4% | Lighting & signalling |
| 1992 | 158 | 82.9% | 17.1% | Brakes |
| 1993 | 129 | 86.8% | 13.2% | Lighting & signalling |
| 1994 | 339 | 83.2% | 16.8% | Lighting & signalling |
| 1995 | 537 | 84.7% | 15.3% | Lighting & signalling |
| 1996 | 703 | 84.1% | 15.9% | Lighting & signalling |
| 1997 | 770 | 82.5% | 17.5% | Lighting & signalling |
| 1998 | 1,076 | 82.0% | 18.0% | Lighting & signalling |
| 1999 | 1,373 | 78.8% | 21.2% | Lighting & signalling |
| 2000 | 2,223 | 78.2% | 21.8% | Lighting & signalling |
| 2001 | 2,564 | 78.9% | 21.1% | Lighting & signalling |
| 2002 | 2,876 | 79.6% | 20.4% | Lighting & signalling |
| 2003 | 4,612 | 80.8% | 19.3% | Lighting & signalling |
| 2004 | 4,368 | 82.2% | 17.8% | Lighting & signalling |
| 2005 | 3,646 | 80.0% | 20.0% | Lighting & signalling |
| 2006 | 6,776 | 82.5% | 17.5% | Brakes |
| 2007 | 8,458 | 81.2% | 18.8% | Brakes |
| 2008 | 6,221 | 81.3% | 18.7% | Brakes |
| 2009 | 5,478 | 80.5% | 19.5% | Brakes |
| 2010 | 5,367 | 83.4% | 16.6% | Brakes |
| 2011 | 5,653 | 84.6% | 15.4% | Brakes |
| 2012 | 7,423 | 84.2% | 15.8% | Brakes |
| 2013 | 5,878 | 86.0% | 14.0% | Tyres |
| 2014 | 9,292 | 90.1% | 9.9% | Tyres |
| 2015 | 12,481 | 89.5% | 10.5% | Tyres |
| 2016 | 15,403 | 90.0% | 10.0% | Tyres |
| 2017 | 13,671 | 90.7% | 9.3% | Tyres |
| 2018 | 13,170 | 93.2% | 6.8% | Tyres |
| 2019 | 11,427 | 93.5% | 6.5% | Tyres |
| 2020 | 2,394 | 93.4% | 6.6% | Tyres |
| 2021 | 1,766 | 93.4% | 6.6% | Tyres |
| 2022 | 1,407 | 94.6% | 5.4% | Tyres |
| 2023 | 766 | 95.0% | 5.0% | Tyres |
| 2024 | 228 | 96.0% | 4.0% | Tyres |
Most common failures (all years)
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 4.6% | 7,439 |
| 2 | Suspension | 4.4% | 7,080 |
| 3 | Brakes | 4.0% | 6,475 |
| 4 | Lighting & signalling | 3.8% | 6,068 |
| 5 | Emissions & environmental | 2.5% | 3,921 |
| 6 | Visibility | 2.0% | 3,223 |
| 7 | Seat belts & restraints | 0.9% | 1,392 |
| 8 | Body, structure & corrosion | 0.8% | 1,352 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Ball joint | 5,092 |
| 2 | Tread depth | 4,765 |
| 3 | Headlamp aim | 2,653 |
| 4 | Rigid brake pipes | 2,454 |
| 5 | Malfunction indicator lamp | 2,262 |
| 6 | Washers | 2,127 |
| 7 | Rbt (sp) | 2,091 |
| 8 | Pins and bushes | 1,924 |
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 | 20.3% | 32,532 |
| 2 | Brakes | 20.3% | 32,474 |
| 3 | Suspension | 13.0% | 20,828 |
| 4 | Emissions & environmental | 5.5% | 8,838 |
| 5 | Other defects | 4.7% | 7,546 |
| 6 | Visibility | 3.7% | 5,865 |
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 | 19,521 | 6.4% |
| 30-60k | 36,703 | 10.4% |
| 60-90k | 35,409 | 13.3% |
| 90-120k | 29,273 | 15.2% |
| 120-150k | 19,987 | 17.2% |
| 150k+ | 18,985 | 17.0% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 110,559 | 13.1% |
| Petrol | 42,228 | 14.0% |
| Hybrid | 7,280 | 7.8% |
| Electric | 102 | 8.8% |
| Other | 34 | 5.9% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 33,805 | 14.3% |
| 2022 | 34,053 | 13.4% |
| 2023 | 32,470 | 12.8% |
| 2024 | 30,760 | 12.8% |
| 2025 | 29,120 | 12.1% |
What to check before buying a Mercedes-Benz S-Class
- Tyres (4.6% 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 (4.4% 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.
- Brakes (4.0% 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.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
What is the MOT pass rate for the Mercedes-Benz S-Class?
86.9% of the 160,208 Mercedes-Benz S-Class MOT tests in this dataset passed, a 13.1% fail rate, across model years 1980–2025.
What does the Mercedes-Benz S-Class most often fail its MOT on?
Tyres, recorded in 4.6% of tests, then suspension (4.4%).
Which S-Class years are best and worst for MOT results?
2022 has the best pass rate at 94.6% and 2000 the weakest at 78.2%, from 1,407 and 2,223 tests respectively.
How much does mileage affect S-Class MOT results?
Fail rates run at 6.4% for cars in the 0-30k band and 17.0% for 150k+, a 10.6-point difference.
Is the hybrid or petrol S-Class more reliable at MOT time?
On MOT-testable defects the hybrid fails 7.8% of the time against 14.0% for the petrol. This covers testable items only, not engine or gearbox reliability.
Methodology & source. Based on 160,208 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.