1986 Mercedes 300 MOT Pass Rate
Pass rate for 300 models manufactured in 1986, based on 3,146 real MOT test results.
Data from official DVSA MOT testing records
This page shows all 300 cars tested in 1986. Want to see how cars built in 1986 hold up over time?
View 1986 Mercedes 300 vintage page → (74.4% current pass rate)1986 Mercedes 300 MOT Analysis
The 1986 Mercedes 300 has an MOT pass rate of 67.3% based on 3,146 tests — slightly above the UK average for UK vehicles. Cars of this vintage present for MOT with an average of 99,983 miles on the odometer. With a 32.7% failure rate, the 1986 300 is rated as "Good" for MOT reliability.
The leading cause of MOT failure for the 1986 Mercedes 300 is Suspension, responsible for 0.9% of failures. 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 range from £200–500. Brakes is the second most common issue at 0.5%. Noise, emissions and leaks follows at 0.4%.
Top failures specific to 1986 models only. The overall 300 page may show different rankings.
What Fails Most
What Fails on This Car?
Click a category to see specific failure items.
View as table
| Rank | Failure Category | Rate (%) | Count |
|---|---|---|---|
| 1 | Suspension | 0.9% | 28 |
| 2 | Brakes | 0.5% | 15 |
| 3 | Noise, Emissions And Leaks | 0.4% | 12 |
| 4 | Tyres | 0.4% | 12 |
| 5 | Body, Chassis, Structure | 0.3% | 10 |
| 6 | Lamps, Reflectors And Electrical Equipment | 0.3% | 10 |
| 7 | Steering | 0.3% | 8 |
| 8 | Visibility | 0.2% | 5 |
Failures per 10,000 Miles
avg. 99,983 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.
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| Category | Rate / 10K mi | Raw % | Count |
|---|---|---|---|
| Suspension | 0.09 | 0.9% | 28 |
| Brakes | 0.05 | 0.5% | 15 |
| Noise, emissions and leaks | 0.04 | 0.4% | 12 |
| Tyres | 0.04 | 0.4% | 12 |
| Body & Structure | 0.03 | 0.3% | 10 |
| Lamps & Electrical | 0.03 | 0.3% | 10 |
| Steering | 0.03 | 0.3% | 8 |
| Visibility | 0.02 | 0.2% | 5 |
Mileage Statistics
Mileage-adjusted failure rate — accounts for how much this model year is typically driven.
About This Data
The 1986 Mercedes 300 has an MOT pass rate of 67.3% based on 3,146 tests — slightly above the UK average for UK vehicles. Cars of this vintage present for MOT with an average of 99,983 miles on the odometer. With a 32.7% failure rate, the 1986 300 is rated as "Good" for MOT reliability.
If you own or are considering buying a 1986 Mercedes 300, you can expect reliable MOT performance overall. Before your MOT, pay particular attention to suspension: 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. With an average mileage of 99,983 miles, these vehicles are in the higher-mileage bracket where wear-related failures become more common.
Suspension — 0.9% of failures
Suspension issues account for 0.9% of MOT failures on 1986 Mercedes 300 models. 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 — 0.5% of failures
Brakes issues account for 0.5% of MOT failures on 1986 Mercedes 300 models. 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).
Noise, emissions and leaks — 0.4% of failures
Noise, emissions and leaks issues account for 0.4% of MOT failures on 1986 Mercedes 300 models. Emissions failures occur when exhaust gases exceed legal limits for carbon monoxide (CO), hydrocarbons (HC), or particulate matter (diesel). Common causes include faulty oxygen sensors, clogged catalytic converters, or DPF issues on diesel vehicles. Typical repair costs: £100–1,000+. Pre-MOT check: If the engine management light is on, get it diagnosed before the MOT. For diesel cars, ensure the DPF has completed a regeneration cycle. Regular servicing and using premium fuel before the test can help.
Based on DVSA anonymised MOT test data (2005–2024). Crown copyright, Open Government Licence v3.0.