Mercedes-Benz S 300 MOT Pass Rate
Overall pass rate across all manufacture years, based on 30 real MOT test results. Failure rate: 36.7%.
Data from official DVSA MOT testing records
Mercedes-Benz S 300 MOT Reliability Overview
The Mercedes-Benz S 300 is a rare vehicle in the UK, with 30 MOT test results recorded in our database spanning 0 manufacture years. It has an overall MOT pass rate of 63.3% and a failure rate of 36.7%, which is around the UK average of approximately 37%.
Based on this data, the Mercedes-Benz S 300 earns a "Average" reliability rating. The average Mercedes-Benz S 300 presents for MOT with approximately 105,910 miles on the clock.
The most common MOT failure for the Mercedes-Benz S 300 is Suspension, affecting 43.3% of all tests. 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. The second most common issue is Brakes at 36.7%. Tyres rounds out the top three at 26.7%. 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 | Suspension | 43.3% | 13 |
| 2 | Brakes | 36.7% | 11 |
| 3 | Tyres | 26.7% | 8 |
| 4 | Lamps, Reflectors And Electrical Equipment | 26.6% | 8 |
| 5 | Driver's View Of The Road | 10.0% | 3 |
| 6 | Noise, Emissions And Leaks | 10.0% | 3 |
| 7 | Non-component Advisories | 6.7% | 2 |
| 8 | Visibility | 6.7% | 2 |
| 9 | Body, Chassis, Structure | 3.3% | 1 |
Failures per 10,000 Miles
avg. 105,910 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 |
|---|---|---|---|
| Suspension | 4.09 | 43.3% | 13 |
| Brakes | 3.46 | 36.7% | 11 |
| Tyres | 2.52 | 26.7% | 8 |
| Lamps & Electrical | 2.52 | 26.6% | 8 |
| Visibility | 1.57 | 16.7% | 5 |
| Noise, emissions and leaks | 0.94 | 10.0% | 3 |
| Non-component advisories | 0.63 | 6.7% | 2 |
| Body & Structure | 0.31 | 3.3% | 1 |
🚗 Similar Cars to Consider
Mileage at MOT
The average Mercedes-Benz S 300 has 105,910 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-Benz S 300 has a mileage-adjusted failure rate of 3.47% per 10,000 miles driven. The average across all makes is 5.38%, so this model is better than average.
About Mercedes-Benz S 300 MOT Data
The Mercedes-Benz S 300 is a rare vehicle in the UK, with 30 MOT test results recorded in our database spanning 0 manufacture years. It has an overall MOT pass rate of 63.3% and a failure rate of 36.7%, which is around the UK average of approximately 37%.
For Mercedes-Benz S 300 owners, these results suggest average reliability — some preparation before MOT can improve pass chances. Focus your pre-MOT checks on suspension and brakes 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 S 300 is likely to perform.
Suspension — 43.3% of failures
Suspension issues account for 43.3% of MOT failures on the Mercedes-Benz S 300. 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.
Brakes — 36.7% of failures
Brakes issues account for 36.7% of MOT failures on the Mercedes-Benz S 300. 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).
Tyres — 26.7% of failures
Tyres issues account for 26.7% of MOT failures on the Mercedes-Benz S 300. Tyre failures include tread depth below the legal minimum of 1.6mm, cuts, bulges, exposed cords, and incorrect tyre pressure. Tyres are one of the most common and easiest-to-prevent MOT failures. Typical repair costs: £50–200 per tyre. Pre-MOT check: Check tread depth with a 20p coin — if the outer band is visible, the tyre is too worn. Look for bulges, cuts, or embedded objects. Ensure all tyres match the recommended size and load rating.
Frequently Asked Questions
What is the MOT pass rate for the Mercedes-Benz S 300?
Based on 30 (based on limited data) MOT tests in our database, the Mercedes-Benz S 300 has an overall pass rate of 63.3% (36.7% fail rate).
What are the most common MOT failures on a Mercedes-Benz S 300?
The top 3 reasons a Mercedes-Benz S 300 fails its MOT are: 1. Suspension (43.3%), 2. Brakes (36.7%), 3. Tyres (26.7%). Check these areas before booking your MOT.
Is the Mercedes-Benz S 300 reliable?
With a 36.7% MOT failure rate, the S 300 is about average compared to the UK average of ~40%.
What should I check before an MOT on my Mercedes-Benz S 300?
Based on failure data, focus on: Suspension (43.3%); Brakes (36.7%); Tyres (26.7%). 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.