Mercedes S350 Cdi MOT Pass Rate
Overall pass rate across all manufacture years, based on 50 real MOT test results. Failure rate: 26.0%.
Data from official DVSA MOT testing records
Mercedes S350 Cdi MOT Reliability Overview
The Mercedes S350 Cdi is a rare vehicle in the UK, with 50 MOT test results recorded in our database spanning 0 manufacture years. It has an overall MOT pass rate of 74.0% and a failure rate of 26.0%, which is above the UK average of approximately 37%.
Based on this data, the Mercedes S350 Cdi earns a "Very Good" reliability rating. The average Mercedes S350 Cdi presents for MOT with approximately 73,276 miles on the clock.
The most common MOT failure for the Mercedes S350 Cdi is Brakes, affecting 32.0% 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 30.0%. Road Wheels rounds out the top three at 10.0%. 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 | 32.0% | 16 |
| 2 | Suspension | 30.0% | 15 |
| 3 | Road Wheels | 10.0% | 5 |
| 4 | Lamps, Reflectors And Electrical Equipment | 8.0% | 4 |
| 5 | Tyres | 4.0% | 2 |
| 6 | Body, Chassis, Structure | 2.0% | 1 |
| 7 | Visibility | 2.0% | 1 |
| 8 | Noise, Emissions And Leaks | 2.0% | 1 |
Failures per 10,000 Miles
avg. 73,276 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 | 4.37 | 32.0% | 16 |
| Suspension | 4.09 | 30.0% | 15 |
| Wheels | 1.36 | 10.0% | 5 |
| Lamps & Electrical | 1.10 | 8.0% | 4 |
| Tyres | 0.55 | 4.0% | 2 |
| Body & Structure | 0.27 | 2.0% | 1 |
| Visibility | 0.27 | 2.0% | 1 |
| Noise, emissions and leaks | 0.27 | 2.0% | 1 |
🚗 Similar Cars to Consider
Mileage at MOT
The average Mercedes S350 Cdi has 73,276 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 S350 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 S350 Cdi MOT Data
The Mercedes S350 Cdi is a rare vehicle in the UK, with 50 MOT test results recorded in our database spanning 0 manufacture years. It has an overall MOT pass rate of 74.0% and a failure rate of 26.0%, which is above the UK average of approximately 37%.
For Mercedes S350 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 S350 Cdi is likely to perform.
Brakes — 32.0% of failures
Brakes issues account for 32.0% of MOT failures on the Mercedes S350 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 — 30.0% of failures
Suspension issues account for 30.0% of MOT failures on the Mercedes S350 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.
Road Wheels — 10.0% of failures
Road Wheels issues account for 10.0% of MOT failures on the Mercedes S350 Cdi. Wheel failures include cracked or severely corroded alloy wheels, missing or loose wheel nuts, and wheels that are insecurely attached. These are safety-critical and relatively rare compared to tyre failures. Typical repair costs: £100–400 per wheel. Pre-MOT check: Visually inspect wheels for cracks, especially around the spokes and rim. Check that all wheel nuts are present and tightened. Look for signs of impact damage on alloy wheels.
Frequently Asked Questions
What is the MOT pass rate for the Mercedes S350 Cdi?
Based on 50 (based on limited data) MOT tests in our database, the Mercedes S350 Cdi has an overall pass rate of 74.0% (26.0% fail rate).
What are the most common MOT failures on a Mercedes S350 Cdi?
The top 3 reasons a Mercedes S350 Cdi fails its MOT are: 1. Brakes (32.0%), 2. Suspension (30.0%), 3. Road Wheels (10.0%). Check these areas before booking your MOT.
Is the Mercedes S350 Cdi reliable?
With a 26.0% MOT failure rate, the S350 Cdi is more reliable than average compared to the UK average of ~40%.
What should I check before an MOT on my Mercedes S350 Cdi?
Based on failure data, focus on: Brakes (32.0%); Suspension (30.0%); Road Wheels (10.0%). 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.