Mercedes-Benz S-Class years to avoid — 69,459 MOT tests ranked

No clear negative outlier after correcting for age. Strongest in the data: 2004 or 2006. The ranking uses 69,459 MOT tests across 17 registration years (2023–2025) and compares each year with all UK cars of the same age.

Every S-Class year, ranked

The age-adjusted MOT index sets 100 as the pass rate of all UK cars registered in the same year and tested in the same calendar year. Higher is better. This prevents an old car being labelled a “bad year” simply because it is old.

RankYearIndexVs same-agePass rateTests
1 2006 Strong 116.8 +16.8 pts 81.3% 3,053
2 2004 Strong 116.3 +16.3 pts 80.6% 1,841
3 2010 114.0 +14.0 pts 81.4% 2,525
4 2003 113.7 +13.7 pts 78.7% 1,900
5 2007 113.4 +13.4 pts 78.5% 3,770
6 2014 113.3 +13.3 pts 89.2% 4,826
7 2008 113.1 +13.1 pts 78.3% 2,835
8 2011 113.0 +13.0 pts 82.2% 2,738
9 2005 112.2 +12.2 pts 76.7% 1,552
10 2009 111.2 +11.2 pts 77.6% 2,506
11 2012 110.7 +10.7 pts 81.9% 3,602
12 2013 110.5 +10.5 pts 83.9% 2,919
13 2015 109.9 +9.9 pts 88.6% 6,465
14 2016 107.1 +7.1 pts 88.4% 8,005
15 2018 105.6 +5.6 pts 92.0% 6,906
16 2017 104.9 +4.9 pts 89.0% 7,087
17 2019 104.4 +4.4 pts 92.8% 6,929

How to use this before buying

  • Rankings describe the cohort, not the car. A cherished older example beats a neglected 2004 one — always run the specific reg through the free MOT history check.
  • Read the advisories. Repeated notes for the same component across years mean the owner has been ignoring it. Decode them in our advisory library.
  • Scan before you pay. A 2-minute OBD scan reveals stored faults the dashboard hides — see our scanner guide.

FAQs

Which S-Class years should I avoid?

No year is a clear negative outlier after correcting for age, so buy on condition and history rather than year.

What is the best S-Class year to buy used?

2004 and 2006 lead the age-adjusted MOT ranking. The score compares each registration year with all UK cars of the same age; the specific car's history and condition still take priority.

Is the S-Class reliable overall?

Across 69,459 tests, the median age-adjusted index is 112.2 (100 equals the pass rate of all cars registered in the same year). Use the spread between years as one signal, then check the individual registration.

Methodology: index = 100 + the model-year cohort’s MOT pass-rate difference versus all UK vehicles registered in the same year and tested in the same calendar year. Class 4 initial tests only; retests excluded; at least 1,500 tests per page. “Inspect” years are below both the same-age baseline and the model’s median index by at least 2 points. Association is not proof of a model-year defect. DVSA anonymised data 2023–2025, OGL v3.0.