Mileage Impact
Pass rates decline with mileage, from 91.63% for vehicles under 30,000 miles to 75.0% for those over 150,000 miles.
| Mileage Band | Pass Rate | Tests |
|---|---|---|
| 0-30k | 91.6% | 251 |
| 30-60k | 90.0% | 518 |
| 60-100k | 85.7% | 238 |
| 100-150k | 83.3% | 18 |
| 150k+ | 75.0% | 4 |
- Mileage bands — failure rates tracked across mileage bands
- Spike detection — >20% increase in failure rate flags a band
- Premature failure bands — 0–30k and 30–60k miles
Competitor Comparison
The 2005 Aston Martin Db9 leads comparable large petrol vehicles with the highest pass rate.
| Rank | Vehicle | Pass Rate | Tests | vs Subject |
|---|---|---|---|---|
| #1 | Aston Martin Db9 | 88.3% | 1,040 | — |
| #2 | Porsche 911 | 84.1% | 2,782 | -4.2pp |
| #3 | Porsche Boxster | 79.5% | 3,249 | -8.8pp |
| #4 | Porsche Cayenne | 71.0% | 1,250 | -17.2pp |
| #5 | Mercedes-Benz Slk | 66.5% | 4,765 | -21.8pp |
| Large Petrol Average | 75.6% |
- Same vehicle class — competitors selected from the same segment
- Fair comparison — same data period and first-time-test scope
Year-over-Year Trend
The Aston Martin Db9 shows consistent improvement in newer model years, with the 2007 model achieving 90.6% compared to 83.65% for the 2004 model.
Improving Trend
Newer model years show higher MOT pass rates, suggesting design and build quality improvements over time.
| Year | Pass Rate | Tests | vs Current |
|---|---|---|---|
| 2004 | 83.7% | 263 | -4.6pp |
| 2005 | 88.3% | 1,040 | — |
| 2006 | 87.6% | 582 | -0.6pp |
| 2007 | 90.6% | 638 | +2.3pp |
- Cross-year tracking — same model tracked across registration years
- Affected year detection — flagged at >120% of overall defect average
Methodology
1,040 MOT tests analysed
Real DVSA data covering 2024-01-01 to 2024-12-30
Independent analysis of official MOT test records, comparing this model’s failure rates against a national baseline to highlight potential weak spots.
Covering 2024-01-01 to 2024-12-30
Licensed under Open Government Licence v3.0
National Baseline Database
Composite of 2005 Class 4 + Aston Martin fleet
642,955 tests analysed + 22,654 make tests
Data Considerations
This analysis identifies statistical patterns in historical MOT data and should be used as one factor in your research. It does not predict future failures or guarantee the condition of any specific vehicle.
- Regional variations reflect test outcomes, not necessarily vehicle quality - factors include testing station practices, local driving conditions, and vehicle maintenance habits.
- Older model years still being tested represent survivorship bias - vehicles that have lasted are likely better-maintained than average.
- Pass rates reflect MOT test outcomes on the test date and may not represent current vehicle condition.
Frequently Asked Questions
Based on 1,040 MOT tests, the 2005 Aston Martin Db9 has a pass rate of 88.27%, which is above the Large Petrol average of 75.61%.
In its segment, rankings by pass rate are: Aston Martin Db9 (88.27%), Porsche 911 (84.11%), Porsche Boxster (79.47%).
Yes, significantly. Pass rates range from 91.63% for vehicles under 30,000 miles to 75.0% for those over 150,000 miles - a 17 percentage point difference.
Check Any Vehicle's MOT History
Search the official DVSA database for MOT test results, advisories, and mileage history for any vehicle.
Check MOT History