Mercedes Benz Ml MOT Failures
An analysis of 179,280 real DVSA MOT tests on the Mercedes Benz Ml — what fails, how often, and how that compares to every other car on UK roads. Generations covered: W163 (1998–2005), W164 (2005–2011), W166 (2011–2019).
Where the Mercedes Benz Ml fails its MOT
The single biggest MOT failure point on the Mercedes Benz Ml is anti-roll bar links worn — this model is 190 times more likely to fail on this item than the average car on UK roads. That makes it an extreme outlier for anyone buying or owning this model. Across 179,280 MOT tests, 12.66% of all Mercedes Benz Ml tests recorded this as a failure.
Suspension failures typically mean worn bushes, drop links, or dampers. These affect handling and tyre wear. Budget £150–£400 per corner at an independent garage for full suspension overhaul.
Other notable weak points include emissions failure (71x the fleet average), suspension pin, bush or joint worn (44x the fleet average), light unit fault (50x the fleet average), and headlight fault (19x the fleet average). These ratios compare the Mercedes Benz Ml's failure rate on each item against the national average for all cars tested — a ratio of 10x means this model fails ten times more often than a typical car.
The failures span 5 categories: Suspension, Exhaust & Emissions, Lights & Electrics, Brakes, Steering. If you're inspecting a Mercedes Benz Ml before purchase, these are the areas to focus on — and if any have been flagged as advisories on a previous MOT, they're likely to become failures in the near future.
How failures change with mileage
The Mercedes Benz Ml's weak points shift as the car covers more miles. Understanding these patterns helps you know what to expect — and what to budget for — at each stage of ownership.
Under 60,000 miles
At this mileage, most failures are either design-related or caused by age rather than wear. Components like bushes and drop links may not have been replaced yet, and original-fit parts can deteriorate even on low-mileage cars that spend a lot of time sitting.
For the Mercedes Benz Ml specifically, the DVSA data shows the most common failures at this mileage are anti-roll bar links worn (49x the average) and brake hoses perished or damaged (20x). headlight fault (19x) and suspension pin, bush or joint worn (18x) also appear frequently.
60,000 to 100,000 miles
This is where routine wear items start to show up. Brake components, tyres, and exhaust parts have done serious work by this point. Cars that have been well serviced will show fewer of these failures — this mileage band is where good maintenance really separates the well-kept from the neglected.
For the Mercedes Benz Ml specifically, the DVSA data shows the most common failures at this mileage are anti-roll bar links worn (190x the average) and emissions failure (71x). light unit fault (50x) and suspension pin, bush or joint worn (44x) also appear frequently.
Over 100,000 miles
High-mileage cars accumulate failures across multiple systems. The key question isn't whether things will need doing — they will — but whether the car has been maintained well enough to keep on top of them. Look for a consistent service history and recent MOT passes with minimal advisories.
For the Mercedes Benz Ml specifically, the DVSA data shows the most common failures at this mileage are stop lamp position or intensity not in accordan... (108x the average) and anti-roll bar links worn (90x). emissions failure (19x) and power steering fault (19x) also appear frequently.
The shift from anti-roll bar links worn at lower mileages to stop lamp position or intensity not in accordan... at higher mileages is typical — early failures tend to be design or factory-related, while high-mileage failures reflect accumulated mechanical wear. A car that's been well maintained will usually dodge the worst of both.
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Known issues beyond the MOT
An MOT only tests roadworthiness at a single point in time — it won't catch developing faults, intermittent problems, or issues that haven't yet reached the failure threshold. These are the issues that Mercedes Benz Ml specialists and owners flag most frequently, drawn from manufacturer technical bulletins, workshop data, and verified owner reports.
Suspension component failure (W163/W164) Dangerous
The ML suffers from premature suspension component failure, particularly control arm bushes, ball joints, and anti-roll bar links. Affects W163, W164; typical independent garage repair cost is £200–£800.
Brake hose deterioration and failure Dangerous
The ML suffers from premature brake hose deterioration, with MOT data showing brake hose failures at up to 17 times the national average on 3.0 CDI models. Affects W164, W166; typical independent garage repair cost is £150–£300.
Handbrake cable damage and adjustment failure Major
The ML experiences frequent handbrake cable failures and adjustment problems, with MOT data showing cable damage at up to 53 times the national average. Affects W164, W166; typical independent garage repair cost is £200–£400.
Diesel emissions system failure (CDI engines) Major
CDI diesel ML models experience frequent emissions system failures, with MOT data showing smoke opacity failures at up to 38 times the national average rate. Affects W163, W164; typical independent garage repair cost is £400–£1,200.
For the complete picture — including repair costs across independent, specialist, and dealer garages — see the full Mercedes Benz Ml common problems breakdown.
What to check before buying a Mercedes Benz Ml
Based on the MOT failure data and known issues above, here's what to prioritise when inspecting a Mercedes Benz Ml:
Suspension — check for anti-roll bar links worn, suspension pin, bush or joint worn. Exhaust & Emissions — check for emissions failure. Lights & Electrics — check for light unit fault, headlight fault.
Beyond the MOT items, ask specifically about suspension component failure and brake hose deterioration and failure. These won't show up on a standard MOT but can be expensive to fix — repairs start from £200. A specialist pre-purchase inspection is worth the investment on this model.
Always check the car's full MOT history for patterns — recurring advisories often become failures within 12 months. And verify the service history to confirm maintenance has been kept up to schedule. Enter any reg into our free car check to see the complete picture.
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Mercedes Benz Ml MOT FAQs
What are the most common MOT failures on a Mercedes Benz Ml?
Based on 179,280 DVSA MOT tests, the most common failure is anti-roll bar links worn — at 190x the national fleet average. Other frequent failures include emissions failure and suspension pin, bush or joint worn.
Is the Mercedes Benz Ml reliable based on MOT data?
The Mercedes Benz Ml has 20 MOT failure categories above the fleet average. Specialists also flag suspension component failure as a concern. A pre-purchase inspection and service history check are recommended.
What MOT failures should I expect at high mileage?
Above 100,000 miles, the Mercedes Benz Ml most commonly fails on stop lamp position or intensity not in accordan... and anti-roll bar links worn. Under 60,000 miles, the main issues are anti-roll bar links worn and brake hoses perished or damaged.
How do I check a Mercedes Benz Ml's MOT history?
Enter the registration number into our free car check above. You'll see every MOT test result, advisories and failures, mileage readings, write-off status, and finance checks.
MOT failure data sourced from DVSA bulk test records via data.gov.uk. Ratios compare this model's failure rate against the national fleet average. Known issues sourced from manufacturer bulletins, specialist workshops, and verified owner reports.