DETHLEFFS UNCLASSIFIED (2021)
Running costs, reliability data, and common problems from 36 real MOT tests.
Annual Cost
£1,695
£141/month
MOT Pass Rate
94%
Excellent
Road Tax
£195
Flat rate/year
Insurance
Grp 25-38
2287cc Diesel
Great Choice
94% pass rate, £1695/year to run. 12 points above average.
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Annual Running Costs
~40 mpg
Flat rate (post-2017)
Low estimate due to excellent reliability
Based on 7,400 miles/year (UK average), current fuel prices, and repair likelihood from MOT data. Insurance not included.
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Reliability Verdict
Excellent reliability. Very few MOT failures. That's 12 points above the national average of 82%. It also outperforms the DETHLEFFS brand average of 90%.
At 5 years old, 94% of DETHLEFFS UNCLASSIFIEDs from 2021 passed their MOT first time in 2026. That's based on 36 tests across the UK. The average mileage at this age is 13,002 miles.
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How Does It Compare?
Mileage Analysis
13,002
Average miles
37,000
Expected for age
The average 2021 DETHLEFFS UNCLASSIFIED has 13,002 miles on the clock, which is significantly below the expected 37,000 miles for a 5-year-old car. Low-mileage examples may have spent time sitting unused, so check for issues like corroded brakes or perished rubber seals.
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Best Year to Buy?
The most reliable year is the 2019 model with a 99% MOT pass rate, while the 2020 model has the lowest at 99%. The 2021 sits between the two at 94%.
DETHLEFFS UNCLASSIFIED by Year
Similar Cars to Consider
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About the 2021 DETHLEFFS UNCLASSIFIED
The 2021 DETHLEFFS UNCLASSIFIED is a large car with a 2287cc diesel engine. 36 of these vehicles were MOT tested in 2026, making it a rare model on UK roads. Among all cars from 2021, the average MOT pass rate is 92%, and this model beats that benchmark.
With an average of 13,002 miles at 5 years old, DETHLEFFS UNCLASSIFIED owners tend to use this car less than the typical driver. Very low mileage could mean the car has been garaged or used only for short trips, which can cause its own issues like battery drain and moisture buildup.
2021 DETHLEFFS UNCLASSIFIED Fuel Costs
The 2287cc diesel engine offers a reasonable balance between performance and economy. Expect around 40 mpg in mixed driving, which works out to roughly £1,245 per year at current diesel prices of 148p per litre (based on 7,400 miles per year). Diesel cars of this age should have their DPF (diesel particulate filter) checked, as replacements can be costly.
What does it cost to own a 2021 DETHLEFFS UNCLASSIFIED?
Total estimated annual running cost is £1,695 (£141/month), broken down as £1245 fuel, £195 road tax, £55 MOT, and £200 predicted repairs. The low repair estimate reflects the excellent 94% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
Buying a Used 2021 DETHLEFFS UNCLASSIFIED
At 5 years old, the DETHLEFFS UNCLASSIFIED offers good value with plenty of life remaining. Most manufacturer warranties will have expired, so a pre-purchase inspection is worth the cost. If you're flexible on year, the 2019 model has the highest pass rate at 99%. Note: with only 36 tests in our data, these figures should be treated as indicative rather than definitive.
Common Issues to Watch For
Based on the 2021 DETHLEFFS UNCLASSIFIED's fuel type, age, and engine size, these are the most likely problem areas to check.
DPF (Diesel Particulate Filter)
Watch outShort journeys clog the DPF. Replacement costs £1,000-£2,500. Check the DPF warning light and ask about driving patterns.
Turbo Wear
Medium riskDiesel turbos work harder and wear faster. Listen for whining noises and check for oil leaks around the turbo housing.
AdBlue System
Medium riskPost-2015 diesels use AdBlue for emissions. Sensor failures and tank heater issues are common. Budget £200-£500 for repairs.
EGR Valve
Low riskExhaust Gas Recirculation valves clog with carbon deposits, causing rough running and poor economy. Cleaning costs £150-£300, replacement £300-£600.
Dual Mass Flywheel
Medium riskLarger diesel engines put extra strain on the dual mass flywheel. Listen for rattling at idle. Replacement with clutch is £800-£1,500.
Service History
Low riskAlways request a full service history. Regular servicing is the single best indicator of how well a car has been maintained, regardless of mileage.
Running Costs Compared
How the 2021 DETHLEFFS UNCLASSIFIED stacks up against similar cars for annual running costs, insurance, and tax.
| Car | Pass Rate | Fuel/yr | Tax/yr | Insurance | Total/yr |
|---|---|---|---|---|---|
| DETHLEFFS UNCLASSIFIED(2021) | 94% | £1245 | £195 | Grp 25-38 | £1695 |
| FORD KUGA(2019) | 91% | £1037 | £190 | Grp 18-32 | £1482-£213 |
| FORD TRANSIT CUSTOM(2019) | 87% | £1037 | £190 | Grp 18-32 | £1632-£63 |
| BMW 118(2020) | 93% | £1037 | £190 | Grp 18-32 | £1482-£213 |
| VOLKSWAGEN T-ROC(2019) | 94% | £1037 | £190 | Grp 18-32 | £1482-£213 |
Estimates based on 7,400 miles/year, current fuel prices, and MOT data. Insurance groups are indicative. Actual costs vary by driver, location, and usage.
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