2009 Mercedes-Benz SLK MOT pass rate: 72.2% (7,333 tests)

2009-registered Mercedes-Benz SLKs passed 72.2% of 7,333 MOT tests in 2023–2025 — 5.8 points better than all UK cars registered in 2009 (66.4%).
72.2%Pass rate, 2009 cars
105.8Age-adjusted index (100 = average)
7,333Tests analysed
66,664 miMedian mileage at test

Is the 2009 SLK getting worse?

Pass rate of 2009-registered cars across recent test years:

Test yearPass rate
202371.1%
+4.2 vs same-age
202473.2%
+7.0 vs same-age
202572.3%
+6.2 vs same-age

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

#SystemDefects recordedShare
1Suspension1,55334.2%
2Brakes91820.2%
3Tyres65314.4%
4Lamps, reflectors and electrical equipment58813.0%
5Visibility2766.1%
6Noise, emissions and leaks2154.7%

All SLK years compared

Registration yearTestsPass rateVs same-ageMedian 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.

Buying a 2009 SLK? Two checks first

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.

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 OGL v3.0.