Mercedes Slk 350 Auto MOT Pass Rate
Overall pass rate across all manufacture years, based on 2,188 real MOT test results. Failure rate: 19.1%.
Data from official DVSA MOT testing records
Mercedes Slk 350 Auto MOT Reliability Overview
The Mercedes Slk 350 Auto is a niche vehicle in the UK, with 2,188 MOT test results recorded in our database spanning 6 manufacture years. It has an overall MOT pass rate of 80.9% and a failure rate of 19.1%, which is well above the UK average of approximately 37%.
Based on this data, the Mercedes Slk 350 Auto earns a "Excellent" reliability rating. The average Mercedes Slk 350 Auto presents for MOT with approximately 45,298 miles on the clock. Manufacture year matters: 2009 models achieve the highest pass rate at 93.5%, while 2004 models have the lowest at 78.9%. This 14.6 percentage point difference suggests notable variation in build quality or component durability across production years.
The most common MOT failure for the Mercedes Slk 350 Auto is Tyres, affecting 12.5% of all tests. 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. The second most common issue is Brakes at 8.8%. Suspension rounds out the top three at 8.0%. 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
Best Year to Buy
📈 How Each Vintage Ages
📉 How Age Affects Reliability
MOT failure rate by vehicle age for the Mercedes Slk 350 Auto. The dashed red line marks when the manufacturer warranty typically expires (3 years).
Line chart showing MOT failure rate by vehicle age from 4 to 11 years, with warranty expiry marked at 3 years.
💡 What does the warranty cliff mean?
The Mercedes Slk 350 Auto shows a relatively stable failure rate after warranty — the change of 0% is negligible. Peak failure occurs at age 9 (24.2% fail rate).
Note: pass rates may improve for very old vehicles due to survivorship bias — only well-maintained cars remain on the road.
Pass Rate by Manufacture Year
* 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 | Tyres | 17.0% | 371 |
| 2 | Brakes | 9.8% | 214 |
| 3 | Lamps, Reflectors And Electrical Equipment | 8.7% | 191 |
| 4 | Suspension | 8.6% | 189 |
| 5 | Driver's View Of The Road | 1.6% | 35 |
| 6 | Registration Plates And Vin | 1.5% | 33 |
| 7 | Steering | 0.9% | 20 |
| 8 | Exhaust, Fuel And Emissions | 0.9% | 19 |
| 9 | Road Wheels | 0.5% | 11 |
| 10 | Seat Belts And Supplementary Restraint Systems | 0.3% | 7 |
| 11 | Identification Of The Vehicle | 0.1% | 2 |
| 12 | Body, Structure And General Items | 0.1% | 2 |
| 13 | Items Not Tested | 0.1% | 2 |
Failures per 10,000 Miles
avg. 45,298 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 |
|---|---|---|---|
| Tyres | 3.74 | 17.0% | 371 |
| Brakes | 2.16 | 9.8% | 214 |
| Lamps & Electrical | 1.93 | 8.7% | 191 |
| Suspension | 1.91 | 8.6% | 189 |
| Visibility | 0.35 | 1.6% | 35 |
| Registration Plates and VIN | 0.33 | 1.5% | 33 |
| Steering | 0.20 | 0.9% | 20 |
| Emissions & Exhaust | 0.19 | 0.9% | 19 |
| Wheels | 0.11 | 0.5% | 11 |
| Seat Belts | 0.07 | 0.3% | 7 |
| Body & Structure | 0.03 | 0.1% | 3 |
| Identification of the vehicle | 0.02 | 0.1% | 2 |
| Items Not Tested | 0.02 | 0.1% | 2 |
| Non-component advisories | 0.01 | 0.0% | 1 |
🚗 Similar Cars to Consider
Mileage at MOT
The average Mercedes Slk 350 Auto has 45,298 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 Slk 350 Auto has a mileage-adjusted failure rate of 4.22% per 10,000 miles driven. The average across all makes is 5.38%, so this model is better than average.
About Mercedes Slk 350 Auto MOT Data
The Mercedes Slk 350 Auto is a niche vehicle in the UK, with 2,188 MOT test results recorded in our database spanning 6 manufacture years. It has an overall MOT pass rate of 80.9% and a failure rate of 19.1%, which is well above the UK average of approximately 37%.
For Mercedes Slk 350 Auto owners, these results suggest a reliable vehicle that generally passes its MOT without major issues. Focus your pre-MOT checks on tyres 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 Slk 350 Auto is likely to perform.
Tyres — 12.5% of failures
Tyres issues account for 12.5% of MOT failures on the Mercedes Slk 350 Auto. 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.
Brakes — 8.8% of failures
Brakes issues account for 8.8% of MOT failures on the Mercedes Slk 350 Auto. 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 — 8.0% of failures
Suspension issues account for 8.0% of MOT failures on the Mercedes Slk 350 Auto. 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.
Frequently Asked Questions
What is the MOT pass rate for the Mercedes Slk 350 Auto?
Based on 2,188 MOT tests in our database, the Mercedes Slk 350 Auto has an overall pass rate of 80.9% (19.1% fail rate).
What are the most common MOT failures on a Mercedes Slk 350 Auto?
The top 3 reasons a Mercedes Slk 350 Auto fails its MOT are: 1. Tyres (12.5%), 2. Brakes (8.8%), 3. Suspension (8.0%). Check these areas before booking your MOT.
Is the Mercedes Slk 350 Auto reliable?
With a 19.1% MOT failure rate, the Slk 350 Auto is more reliable than average compared to the UK average of ~40%.
What should I check before an MOT on my Mercedes Slk 350 Auto?
Based on failure data, focus on: Tyres (12.5%); Brakes (8.8%); Suspension (8.0%). 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.