2004 Mercedes-Benz Clk MOT pass rate: 66.8% (11,737 tests)
Is the 2004 Clk getting worse?
Pass rate of 2004-registered cars across recent test years:
| Test year | Pass rate | |
|---|---|---|
| 2023 | 65.5% +1.6 vs same-age |
|
| 2024 | 67.1% +3.0 vs same-age |
|
| 2025 | 68.4% +3.1 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 2004 Clk
| # | System | Defects recorded | Share |
|---|---|---|---|
| 1 | Suspension | 3,816 | 29.5% |
| 2 | Lamps, reflectors and electrical equipment | 2,707 | 21.0% |
| 3 | Brakes | 2,214 | 17.1% |
| 4 | Tyres | 1,246 | 9.6% |
| 5 | Noise, emissions and leaks | 724 | 5.6% |
| 6 | Visibility | 591 | 4.6% |
All Clk years compared
| Registration year | Tests | Pass rate | Vs same-age | Median mileage |
|---|---|---|---|---|
| 2001 | 3,999 | 74.7% | +8.1 pts | 99,251 |
| 2002 | 4,823 | 71.7% | +6.1 pts | 104,282 |
| 2003 | 8,746 | 69.5% | +4.5 pts | 103,162 |
| 2004 (this page) | 11,737 | 66.8% | +2.5 pts | 102,146 |
| 2005 | 11,731 | 67.3% | +2.8 pts | 104,069 |
| 2006 | 9,603 | 66.8% | +2.4 pts | 103,168 |
| 2007 | 11,034 | 66.0% | +0.9 pts | 102,520 |
| 2008 | 7,785 | 66.2% | +1.1 pts | 100,330 |
| 2009 | 8,628 | 65.2% | -1.2 pts | 93,910 |
Weighing up which year to buy? See the full ranking: Mercedes-Benz Clk years to avoid.
- Free MOT history checkThe exact car’s failures, advisories and mileage trail — sellers can’t edit it
- Topdon OBD2 scannersTopdon diagnostic scanners with full-system readouts
- XTOOL diagnostic toolsXTOOL code readers for petrol and diesel cars
- Autel UK testersAutel professional-grade diagnostic testers
FAQs
Is a 2004 Mercedes-Benz Clk reliable?
2004-registered examples passed 66.8% of their MOT tests (11,737 tests, 2023–2025), +2.5 points versus all UK cars registered in the same year. At roughly 22 years old with a median 102,146 miles, condition now varies car by car — always check the individual MOT history.
What mileage is too high for a 2004 Clk?
The median tested example shows 102,146 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.
Should I buy the petrol or diesel 2004 Clk?
In this cohort petrols pass 67.4% of tests against 61.2% for diesels. Mileage and use can explain part of that gap, so treat it as a reason to inspect DPF and emissions history, not a fuel-type verdict.
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.