MERCEDES SL 400 GRAND EDITION AUTO (2020)
Running costs, common problems, and reliability data based on 113 real MOT tests in 2024.
MOT Pass Rate
96%
Total Tests (2024)
113
Avg Mileage
15,215 mi
Est. Annual Cost
£2,037
Is the 2020 MERCEDES SL 400 GRAND EDITION AUTO reliable?
Excellent reliability. Very few MOT failures. That's 14 points above the national average of 82%. It also outperforms the MERCEDES brand average of 87%.
At 4 years old, 96% of MERCEDES SL 400 GRAND EDITION AUTOs from 2020 passed their MOT first time in 2024. That's based on 113 tests across the UK. The average mileage at this age is 15,215 miles.
How does the 2020 MERCEDES SL 400 GRAND EDITION AUTO compare?
Mileage Analysis
The average 2020 MERCEDES SL 400 GRAND EDITION AUTO has 15,215 miles on the clock, which is below the expected 29,600 miles for a 4-year-old car. This suggests lighter use than average, which generally means less wear on major components.
How much does a 2020 MERCEDES SL 400 GRAND EDITION AUTO cost to run?
Based on 7,400 miles/year (UK average), current fuel prices, and repair likelihood from MOT pass rate data. Insurance not included.
MERCEDES SL 400 GRAND EDITION AUTO by Year
Checking a specific MERCEDES SL 400 GRAND EDITION AUTO?
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About the 2020 MERCEDES SL 400 GRAND EDITION AUTO
The 2020 MERCEDES SL 400 GRAND EDITION AUTO is a large car with a 2996cc petrol engine. 113 of these vehicles were MOT tested in 2024, making it a rare model on UK roads. It ranks in the top 15% of all 2020 cars for reliability.
With an average of 15,215 miles at 4 years old, MERCEDES SL 400 GRAND EDITION AUTO owners tend to use this car less than the typical driver.
2020 MERCEDES SL 400 GRAND EDITION AUTO Fuel Costs
The 2996cc petrol engine is on the larger side, so fuel won't be this car's strong point. Expect around 30 mpg in mixed driving, which works out to roughly £1,592 per year at current petrol prices of 142p per litre (based on 7,400 miles per year).
What does it cost to own a 2020 MERCEDES SL 400 GRAND EDITION AUTO?
Total estimated annual running cost is £2,037 (£170/month), broken down as £1592 fuel, £190 road tax, £55 MOT, and £200 predicted repairs. The low repair estimate reflects the excellent 96% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
Buying a Used 2020 MERCEDES SL 400 GRAND EDITION AUTO
At 4 years old, the MERCEDES SL 400 GRAND EDITION AUTO offers good value with plenty of life remaining. Most manufacturer warranties will have expired, so a pre-purchase inspection is worth the cost.
Alternatives to the 2020 MERCEDES SL 400 GRAND EDITION AUTO
The MERCEDES SL 400 GRAND EDITION AUTO is actually the most reliable option among similar petrol large cars from this era. Here are comparable petrol cars with similar engines:
- BMW 5 SERIES (2018) 91% pass rate (-5%) from 40,272 tests
- LAND ROVER RANGE ROVER SPORT (2018) 93% pass rate (-3%) from 34,257 tests
- BMW X3 (2019) 92% pass rate (-4%) from 32,937 tests
- MERCEDES GLC (2019) 93% pass rate (-3%) from 30,341 tests