Mercedes 518 Cdi MOT Pass Rate
Overall pass rate across all manufacture years, based on 61 real MOT test results. Failure rate: 32.8%.
Data from official DVSA MOT testing records
Mercedes 518 Cdi MOT Reliability Overview
The Mercedes 518 Cdi is a rare vehicle in the UK, with 61 MOT test results recorded in our database spanning 0 manufacture years. It has an overall MOT pass rate of 67.2% and a failure rate of 32.8%, which is slightly above the UK average of approximately 37%.
Based on this data, the Mercedes 518 Cdi earns a "Good" reliability rating. The average Mercedes 518 Cdi presents for MOT with approximately 92,438 miles on the clock.
The most common MOT failure for the Mercedes 518 Cdi is Brakes, affecting 42.6% of all tests. Brake-related failures include worn brake pads, corroded brake discs, leaking brake lines, and faulty brake servos. These are safety-critical components — any brake deficiency will result in an MOT fail. The second most common issue is Suspension at 14.8%. Body, chassis, structure rounds out the top three at 9.8%. Together, these top 3 failure categories account for a significant portion of all MOT failures for this model.
Top failures across all manufacture years combined. Individual year pages may show different top failures.
What Fails Most
* High Fail Rate badge indicates an MOT pass rate below 65% (failure rate above 35%).
What Fails on This Car?
Click a category to see specific failure items.
View as table
| Rank | Failure Category | Rate (%) | Count |
|---|---|---|---|
| 1 | Brakes | 42.6% | 26 |
| 2 | Lamps, Reflectors And Electrical Equipment | 16.4% | 10 |
| 3 | Suspension | 14.8% | 9 |
| 4 | Body, Chassis, Structure | 9.8% | 6 |
| 5 | Noise, Emissions And Leaks | 9.8% | 6 |
| 6 | Tyres | 8.2% | 5 |
| 7 | Steering | 6.6% | 4 |
| 8 | Driver's View Of The Road | 4.9% | 3 |
| 9 | Registration Plates And Vin | 3.3% | 2 |
| 10 | Visibility | 3.3% | 2 |
| 11 | Body, Structure And General Items | 1.6% | 1 |
| 12 | Identification Of The Vehicle | 1.6% | 1 |
| 13 | Non-component Advisories | 1.6% | 1 |
Failures per 10,000 Miles
avg. 92,438 miFor every 10,000 miles driven, this shows what percentage of MOT tests fail for each category. This accounts for how far cars are actually driven, not just raw pass/fail counts.
View as table
| Category | Rate / 10K mi | Raw % | Count |
|---|---|---|---|
| Brakes | 4.61 | 42.6% | 26 |
| Lamps & Electrical | 1.78 | 16.4% | 10 |
| Suspension | 1.60 | 14.8% | 9 |
| Body & Structure | 1.24 | 11.4% | 7 |
| Noise, emissions and leaks | 1.06 | 9.8% | 6 |
| Tyres | 0.89 | 8.2% | 5 |
| Visibility | 0.88 | 8.2% | 5 |
| Steering | 0.71 | 6.6% | 4 |
| Registration Plates and VIN | 0.35 | 3.3% | 2 |
| Identification of the vehicle | 0.18 | 1.6% | 1 |
| Non-component advisories | 0.18 | 1.6% | 1 |
🚗 Similar Cars to Consider
Mileage at MOT
The average Mercedes 518 Cdi has 92,438 miles when tested for MOT.
📊 Mileage-Adjusted Failure Rate
How often this car fails MOT relative to how much it's driven — a fairer comparison than raw pass rate.
The Mercedes 518 Cdi has a mileage-adjusted failure rate of 3.55% per 10,000 miles driven. The average across all makes is 5.38%, so this model is better than average.
About Mercedes 518 Cdi MOT Data
The Mercedes 518 Cdi is a rare vehicle in the UK, with 61 MOT test results recorded in our database spanning 0 manufacture years. It has an overall MOT pass rate of 67.2% and a failure rate of 32.8%, which is slightly above the UK average of approximately 37%.
For Mercedes 518 Cdi owners, these results suggest a reliable vehicle that generally passes its MOT without major issues. Focus your pre-MOT checks on brakes and suspension for the best chance of a first-time pass. Use our detailed year-by-year breakdown and failure analysis below to understand how your specific 518 Cdi is likely to perform.
Brakes — 42.6% of failures
Brakes issues account for 42.6% of MOT failures on the Mercedes 518 Cdi. Brake-related failures include worn brake pads, corroded brake discs, leaking brake lines, and faulty brake servos. These are safety-critical components — any brake deficiency will result in an MOT fail. Typical repair costs: £150–400. Pre-MOT check: Listen for squealing or grinding noises. Check brake pedal feel — if it feels spongy or goes to the floor, have the system inspected immediately. Look at brake pad thickness through the wheel spokes (minimum 3mm).
Suspension — 14.8% of failures
Suspension issues account for 14.8% of MOT failures on the Mercedes 518 Cdi. Suspension failures typically involve worn bushes, leaking shock absorbers, broken coil springs, and damaged suspension arms. These affect ride quality, tyre wear, and road holding. Typical repair costs: £200–500. Pre-MOT check: Look for uneven tyre wear, listen for clunking over bumps, and check if the car pulls to one side. A bouncy ride suggests worn shock absorbers. Visually inspect coil springs for cracks.
Body, chassis, structure — 9.8% of failures
Body, chassis, structure issues account for 9.8% of MOT failures on the Mercedes 518 Cdi. Body and structure failures include excessive corrosion, sharp edges, loose panels, and damage to the vehicle frame. Rust is the primary concern, especially on older vehicles or those exposed to road salt. Typical repair costs: £100–500+. Pre-MOT check: Inspect sills, wheel arches, door bottoms, and the chassis for rust. Surface rust is acceptable but structural corrosion or holes will fail. Check that all doors, bonnet, and boot close securely.
Frequently Asked Questions
What is the MOT pass rate for the Mercedes 518 Cdi?
Based on 61 (based on limited data) MOT tests in our database, the Mercedes 518 Cdi has an overall pass rate of 67.2% (32.8% fail rate).
What are the most common MOT failures on a Mercedes 518 Cdi?
The top 3 reasons a Mercedes 518 Cdi fails its MOT are: 1. Brakes (42.6%), 2. Suspension (14.8%), 3. Body, chassis, structure (9.8%). Check these areas before booking your MOT.
Is the Mercedes 518 Cdi reliable?
With a 32.8% MOT failure rate, the 518 Cdi is more reliable than average compared to the UK average of ~40%.
What should I check before an MOT on my Mercedes 518 Cdi?
Based on failure data, focus on: Brakes (42.6%); Suspension (14.8%); Body, chassis, structure (9.8%). These are the areas most likely to cause a fail. Also check all lights, tyres (minimum 1.6mm tread), and windscreen condition — these are quick wins that apply to all cars.
Based on DVSA anonymised MOT test data (2005–2024). Crown copyright, Open Government Licence v3.0.