MERCEDES G 400 AMG LINE PREM D 4MATIC A (2021)
Running costs, common problems, and reliability data based on 217 real MOT tests in 2024.
MOT Pass Rate
95%
Total Tests (2024)
217
Avg Mileage
28,762 mi
Est. Annual Cost
£1,690
Is the 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A reliable?
Excellent reliability. Very few MOT failures. That's 13 points above the national average of 82%. It also outperforms the MERCEDES brand average of 87%.
At 3 years old, 95% of MERCEDES G 400 AMG LINE PREM D 4MATIC As from 2021 passed their MOT first time in 2024. That's based on 217 tests across the UK. The average mileage at this age is 28,762 miles.
How does the 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A compare?
Mileage Analysis
The average 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A has 28,762 miles on the clock, which is above the expected 22,200 miles for a 3-year-old car. Higher-mileage cars often have more motorway miles, which is generally less harmful than stop-start urban driving.
How much does a 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A 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.
Checking a specific MERCEDES G 400 AMG LINE PREM D 4MATIC A?
Enter the reg plate to see its individual MOT history, mileage verification, and predicted costs.
About the 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A
The 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A is a large car with a 2925cc diesel engine. 217 of these vehicles were MOT tested in 2024, making it a less common model in the UK market. Among all cars from 2021, the average MOT pass rate is 92%, and this model beats that benchmark.
With an average of 28,762 miles at 3 years old, MERCEDES G 400 AMG LINE PREM D 4MATIC A owners cover more miles than the average driver.
2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A Fuel Costs
The 2925cc 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).
What does it cost to own a 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A?
Total estimated annual running cost is £1,690 (£141/month), broken down as £1245 fuel, £190 road tax, £55 MOT, and £200 predicted repairs. The low repair estimate reflects the excellent 95% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
Buying a Used 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A
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.
Alternatives to the 2021 MERCEDES G 400 AMG LINE PREM D 4MATIC A
The MERCEDES G 400 AMG LINE PREM D 4MATIC A is actually the most reliable option among similar diesel large cars from this era. Here are comparable diesel cars with similar engines:
- MERCEDES E (2019) 90% pass rate (-5%) from 41,000 tests
- FORD RANGER (2019) 87% pass rate (-8%) from 32,194 tests
- AUDI Q5 (2019) 93% pass rate (-2%) from 24,241 tests
- AUDI A5 (2019) 90% pass rate (-5%) from 22,290 tests