DETHLEFFS UNCLASSIFIED (2017)
Running costs, reliability data, and common problems from 43 real MOT tests.
Annual Cost
£1,845
£154/month
MOT Pass Rate
88%
Good
Road Tax
£195
Flat rate/year
Insurance
Grp 30-42
2998cc Diesel
Solid Option
88% pass rate, £1845/year to run. 6 points above average.
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Annual Running Costs
~40 mpg
Flat rate (post-2017)
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
Good reliability. Occasional issues but generally solid. That's 6 points above the national average of 82%.
At 9 years old, 88% of DETHLEFFS UNCLASSIFIEDs from 2017 passed their MOT first time in 2026. That's based on 43 tests across the UK. The average mileage at this age is 21,237 miles.
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How Does It Compare?
Mileage Analysis
21,237
Average miles
66,600
Expected for age
The average 2017 DETHLEFFS UNCLASSIFIED has 21,237 miles on the clock, which is significantly below the expected 66,600 miles for a 9-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 2017 sits between the two at 88%.
DETHLEFFS UNCLASSIFIED by Year
Similar Cars to Consider
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About the 2017 DETHLEFFS UNCLASSIFIED
The 2017 DETHLEFFS UNCLASSIFIED is a large car with a 2998cc diesel engine. 43 of these vehicles were MOT tested in 2026, making it a rare model on UK roads. Among all cars from 2017, the average MOT pass rate is 87%, and this model beats that benchmark.
With an average of 21,237 miles at 9 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.
2017 DETHLEFFS UNCLASSIFIED Fuel Costs
The 2998cc diesel engine is on the larger side, so fuel won't be this car's strong point. 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 2017 DETHLEFFS UNCLASSIFIED?
Total estimated annual running cost is £1,845 (£154/month), broken down as £1245 fuel, £195 road tax, £55 MOT, and £350 predicted repairs. Repair costs are moderate, reflecting the 88% pass rate. Keeping on top of servicing will help avoid surprises.
Buying a Used 2017 DETHLEFFS UNCLASSIFIED
At 9 years old, this is a solid used buy if you find one with good service history. Depreciation has levelled off, so you won't lose much more value. Focus on condition over mileage. If you're flexible on year, the 2019 model has the highest pass rate at 99%. Note: with only 43 tests in our data, these figures should be treated as indicative rather than definitive.
Common Issues to Watch For
Based on the 2017 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
Watch outDiesel 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
Watch outExhaust Gas Recirculation valves clog with carbon deposits, causing rough running and poor economy. Cleaning costs £150-£300, replacement £300-£600.
Dual Mass Flywheel
Watch outLarger diesel engines put extra strain on the dual mass flywheel. Listen for rattling at idle. Replacement with clutch is £800-£1,500.
Suspension Wear
Medium riskShock absorbers, springs, and anti-roll bar links typically need attention around this age. Listen for clunks over bumps and check for uneven tyre wear.
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 2017 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(2017) | 88% | £1245 | £195 | Grp 30-42 | £1845 |
| MERCEDES E(2019) | 90% | £1245 | £190 | Grp 30-42 | £1690-£155 |
| MERCEDES GLC(2018) | 91% | £1245 | £190 | Grp 30-42 | £1690-£155 |
| AUDI A5(2017) | 89% | £1245 | £190 | Grp 30-42 | £1840-£5 |
| FORD RANGER(2019) | 87% | £1245 | £190 | Grp 35-50 | £1840-£5 |
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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