2009 Mercedes-Benz SLK MOT pass rate: 72.2% (7,333 tests)
Is the 2009 SLK getting worse?
Pass rate of 2009-registered cars across recent test years:
Scroll horizontally to read every trend column.
| Test year | Pass rate | Pass-rate bar |
|---|---|---|
| 2023 | 71.1% +4.2 vs same-age |
71.1% visual scale |
| 2024 | 73.2% +7.0 vs same-age |
73.2% visual scale |
| 2025 | 72.3% +6.2 vs same-age |
72.3% visual scale |
The raw rate normally falls as cars age. The “vs same-age” figure compares this cohort with all UK cars registered in the same year, so normal ageing is not mistaken for a bad model year.
What fails on a 2009 SLK
Scroll horizontally to read every failure column.
| # | System | Defects recorded | Share |
|---|---|---|---|
| 1 | Suspension | 1,553 | 34.2% |
| 2 | Brakes | 918 | 20.2% |
| 3 | Tyres | 653 | 14.4% |
| 4 | Lamps, reflectors and electrical equipment | 588 | 13.0% |
| 5 | Visibility | 276 | 6.1% |
| 6 | Noise, emissions and leaks | 215 | 4.7% |
All SLK years compared
Scroll horizontally to compare every registration-year column.
| Registration year | Tests | Pass rate | Vs same-age | Median mileage |
|---|---|---|---|---|
| 2001 | 6,218 | 76.8% | +10.1 pts | 87,028 |
| 2002 | 5,528 | 77.7% | +11.9 pts | 84,096 |
| 2003 | 5,058 | 73.6% | +8.5 pts | 81,064 |
| 2004 | 8,890 | 70.1% | +5.7 pts | 81,784 |
| 2005 | 13,925 | 71.2% | +6.7 pts | 79,516 |
| 2006 | 10,788 | 71.6% | +7.2 pts | 77,638 |
| 2007 | 10,293 | 71.2% | +6.1 pts | 72,692 |
| 2008 | 9,411 | 71.4% | +6.3 pts | 71,853 |
| 2009 (this page) | 7,333 | 72.2% | +5.8 pts | 66,664 |
| 2010 | 6,106 | 73.6% | +6.2 pts | 62,311 |
| 2011 | 7,403 | 78.6% | +9.4 pts | 57,773 |
| 2012 | 16,341 | 77.3% | +6.1 pts | 60,294 |
| 2013 | 13,440 | 77.6% | +4.3 pts | 58,930 |
| 2014 | 14,281 | 80.7% | +4.8 pts | 51,701 |
| 2015 | 14,302 | 83.2% | +4.5 pts | 45,175 |
| 2016 | 3,688 | 85.4% | +4.1 pts | 39,182 |
Weighing up which year to buy? See the full ranking: Mercedes-Benz SLK years to avoid.
- Free MOT history checkThe exact car’s failures, advisories and mileage trail — sellers can’t edit it
FAQs
Is a 2009 Mercedes-Benz SLK reliable?
2009-registered examples passed 72.2% of their MOT tests (7,333 tests, 2023–2025), +5.8 points versus all UK cars registered in the same year. At roughly 17 years old with a median 66,664 miles, condition now varies car by car — always check the individual MOT history.
What mileage is too high for a 2009 SLK?
The median tested example shows 66,664 miles. Anything far beyond that isn't automatically bad — a motorway-mile car with consistent service records often beats a low-mileage school-run car — but price accordingly and scrutinise the mileage trail for gaps or drops.
Before you agree to the work
A fault or an advisory is a quote waiting to happen. These pages set out what a garage has to tell you, what a comparable written quote should include, and what you can do if the bill is not what you agreed.
- When a repair costs more than the car — what a comparable quote should include, plus any verified UK figures we have sourced.
- Estimates, quotes and extra work — what a price has to cover, and when a garage may charge more than it first said.
- What a diagnostic test costs — what the fee should include, and when it should come off the repair.
- Tools — when to buy and when to skip — how to choose a diagnostic tool, and when a garage visit is cheaper than owning one.
- Choosing a garage you can check — what to verify before you hand over the keys.
- Your rights after a car repair — what to do when the work is not right, and how to put it in writing.
Source: DVSA Anonymised MOT tests and results, 2023–2025 extracts (96 million Class 4 initial tests; retests excluded). Only vehicles old enough for a routine first MOT are included. Age-adjusted figures compare the model-year cohort with all vehicles of the same registration year tested in the same calendar year. Contains public sector information licensed under the Open Government Licence v3.0.