MERCEDES SL 400 GRAND EDITION AUTO (2021)
Running costs, common problems, and reliability data based on 34 real MOT tests in 2024.
MOT Pass Rate
85%
Total Tests (2024)
34
Avg Mileage
18,981 mi
Est. Annual Cost
£2,187
Is the 2021 MERCEDES SL 400 GRAND EDITION AUTO reliable?
Good reliability. Occasional issues but generally solid. That's close to the national average of 82%.
At 3 years old, 85% of MERCEDES SL 400 GRAND EDITION AUTOs from 2021 passed their MOT first time in 2024. That's based on 34 tests across the UK. The average mileage at this age is 18,981 miles.
How does the 2021 MERCEDES SL 400 GRAND EDITION AUTO compare?
Mileage Analysis
The average 2021 MERCEDES SL 400 GRAND EDITION AUTO has 18,981 miles on the clock, which is in line with the expected 22,200 miles for a 3-year-old car, suggesting normal everyday use.
How much does a 2021 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 2021 MERCEDES SL 400 GRAND EDITION AUTO
The 2021 MERCEDES SL 400 GRAND EDITION AUTO is a large car with a 2996cc petrol engine. 34 of these vehicles were MOT tested in 2024, making it a rare model on UK roads. It sits in the bottom 93% of 2021 cars for MOT pass rates.
With an average of 18,981 miles at 3 years old, MERCEDES SL 400 GRAND EDITION AUTO owners drive about as much as the UK average.
2021 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 2021 MERCEDES SL 400 GRAND EDITION AUTO?
Total estimated annual running cost is £2,187 (£182/month), broken down as £1592 fuel, £190 road tax, £55 MOT, and £350 predicted repairs. Repair costs are moderate, reflecting the 85% pass rate. Keeping on top of servicing will help avoid surprises.
Buying a Used 2021 MERCEDES SL 400 GRAND EDITION AUTO
At 3 years old, this is still relatively fresh. You may find examples with remaining manufacturer warranty. Depreciation is slowing but hasn't bottomed out yet. Note: with only 34 tests in our data, these figures should be treated as indicative rather than definitive.
Alternatives to the 2021 MERCEDES SL 400 GRAND EDITION AUTO
If reliability is your priority, there are 4 similar cars with a higher MOT pass rate. Here are comparable petrol cars with similar engines:
- BMW 5 SERIES (2019) 92% pass rate (+7%) from 33,766 tests
- BMW X3 (2019) 92% pass rate (+7%) from 32,937 tests
- MERCEDES GLC (2019) 93% pass rate (+8%) from 30,341 tests
- BMW X5 (2019) 92% pass rate (+7%) from 23,506 tests