Mercedes-Benz CLS years to avoid: 2017, 2018, 2019
Last updated · OBDCode UK editorial
Every CLS 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.
Scroll horizontally to read every ranking column.
| Rank | Year | Index | Vs same-age | Pass rate | Tests |
|---|---|---|---|---|---|
| 1 | 2005 Strong | 111.6 | +11.6 pts | 76.1% | 2,789 |
| 2 | 2006 | 109.4 | +9.4 pts | 73.9% | 4,152 |
| 3 | 2011 | 107.9 | +7.9 pts | 77.1% | 3,480 |
| 4 | 2007 | 107.1 | +7.1 pts | 72.2% | 5,062 |
| 5 | 2008 | 106.7 | +6.7 pts | 71.9% | 4,020 |
| 6 | 2012 | 105.6 | +5.6 pts | 76.8% | 3,312 |
| 7 | 2015 | 103.5 | +3.5 pts | 82.2% | 8,599 |
| 8 | 2010 | 103.1 | +3.1 pts | 70.5% | 3,175 |
| 9 | 2009 | 102.9 | +2.9 pts | 69.3% | 3,249 |
| 10 | 2013 | 102.5 | +2.5 pts | 75.8% | 9,119 |
| 11 | 2014 | 101.7 | +1.7 pts | 77.6% | 5,329 |
| 12 | 2016 | 100.9 | +0.9 pts | 82.2% | 6,264 |
| 13 | 2017 Inspect | 99.2 | -0.8 pts | 83.3% | 4,439 |
| 14 | 2018 Inspect | 97.6 | -2.4 pts | 83.9% | 2,877 |
| 15 | 2019 Inspect | 95.7 | -4.3 pts | 84.1% | 3,212 |
Why 2017 and 2018 and 2019 rank lower
The 2017 cohort passes 83.3% of tests (-0.8 points versus same-age cars) at a median 55,712 miles, with tyres the leading failure system. The 2018 cohort passes 83.9% of tests (-2.4 points versus same-age cars) at a median 46,578 miles, with tyres the leading failure system. The 2019 cohort passes 84.1% of tests (-4.3 points versus same-age cars) at a median 39,081 miles, with tyres the leading failure system. This is population-level evidence, not a known-fault list: service history, engine version and the individual MOT record can outweigh the registration-year average.
What happened next on this model
Year rankings are age-adjusted pass rates. The figures below are a same-vehicle follow-up for certificate lines that appear often enough on this model (at least 200 cars). They are not a repair quote and they do not isolate a turbo, DSG, or clutch part.
- Ball joint has slight play — 551 cars · 7.1% failed the same item the next year · 23.0% were not tested again
- Rigid brake pipes corroded, covered in grease or other material — 1,806 cars · 5.4% failed the same item the next year · 14.7% were not tested again
- Condition has a cut but not deep enough to reach the ply or cords — 386 cars · 4.4% failed the same item the next year · 7.8% were not tested again
- Tread depth worn close to legal limit/worn on edge — 2,992 cars · 3.0% failed the same item the next year · 13.3% were not tested again
- Condition slightly damaged — 213 cars · 2.8% failed the same item the next year · 6.6% were not tested again
National rankings for the not-retested gap: cars not tested again. Repair-hold rates: repairs that did not hold.
How to use this before buying
- Rankings describe the cohort, not the car. A cherished 2017 example beats a neglected 2005 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.
- Fuel matters on this model. The diesel deficit (5.0 points) usually traces to DPF and emissions kit on low-mileage use — check for P2463-type soot codes on the test drive.
- Scan before you pay. A 2-minute OBD scan reveals stored faults the dashboard hides — see our scanner guide.
FAQs
Which CLS years should I avoid?
Based on 69,078 MOT tests adjusted against cars of the same age, 2017, 2018, 2019 are the lower-scoring outliers. That is a prompt for closer inspection, not proof that every car from those years is bad.
What is the best CLS year to buy used?
2005 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 CLS reliable overall?
Across 69,078 tests, the median age-adjusted index is 103.1 (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.
What data is required before a years-to-avoid guide is published?
We publish a guide only when a model has at least five registration-year cohorts old enough for a routine first MOT, each based on at least 1,500 Class 4 initial MOT tests pooled across the stated DVSA extract years, and at least 60,000 tests across those cohorts. From the models that pass those gates, this release includes the 220 models with the largest pooled samples. Retests are excluded.
How are the Strong and Inspect labels assigned?
Strong considers only the two highest-ranked registration-year cohorts and labels either one that is within 1.5 index points of the best. Inspect considers only the three lowest-ranked cohorts and labels a year only when its index is no higher than 100 and at least 2 points below the model median. Counts are MOT test records, not unique vehicles.
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. Pass rate uses DVSA result codes (P + PRS) ÷ (P + PRS + F): passes and passes after rectification at the test divided by those outcomes plus failures. Class 4 initial-test records only; retests excluded; at least 1,500 records per registration-year cohort. “Strong” considers the top two cohorts within 1.5 index points of the best. “Inspect” considers only the bottom three cohorts, then requires an index no higher than 100 and at least 2 points below the model median. Counts are test records, not unique vehicles. Association is not proof of a model-year defect. Source: DVSA Anonymised MOT tests and results, 2023–2025 extracts. Contains public sector information licensed under the Open Government Licence v3.0.