MERCEDES GLS (2017)
Running costs, common problems, and reliability data based on 1,425 real MOT tests in 2024.
MOT Pass Rate
92%
Total Tests (2024)
1,425
Avg Mileage
62,721 mi
Est. Annual Cost
£1,690
Is the 2017 MERCEDES GLS reliable?
Excellent reliability. Very few MOT failures. That's 10 points above the national average of 82%. It also outperforms the MERCEDES brand average of 87%.
At 7 years old, 92% of MERCEDES GLSs from 2017 passed their MOT first time in 2024. That's based on 1,425 tests across the UK. The average mileage at this age is 62,721 miles.
How does the 2017 MERCEDES GLS compare?
Mileage Analysis
The average 2017 MERCEDES GLS has 62,721 miles on the clock, which is above the expected 51,800 miles for a 7-year-old car. Higher-mileage cars often have more motorway miles, which is generally less harmful than stop-start urban driving.
Best year to buy a MERCEDES GLS?
The most reliable year is the 2016 model with a 93% MOT pass rate, while the 2018 model has the lowest at 90%. The 2017 sits between the two at 92%.
How much does a 2017 MERCEDES GLS 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 GLS by Year
Checking a specific MERCEDES GLS?
Enter the reg plate to see its individual MOT history, mileage verification, and predicted costs.
About the 2017 MERCEDES GLS
The 2017 MERCEDES GLS is a large car with a 2987cc diesel engine. 1,425 of these vehicles were MOT tested in 2024, making it a reasonably common sight on UK roads. It ranks in the top 25% of all 2017 cars for reliability.
With an average of 62,721 miles at 7 years old, MERCEDES GLS owners cover more miles than the average driver.
2017 MERCEDES GLS Fuel Costs
The 2987cc 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 MERCEDES GLS?
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 92% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
MERCEDES GLS Reliability Trend
The MERCEDES GLS has maintained consistent MOT pass rates across model years, varying by only 2 percentage points.
Buying a Used 2017 MERCEDES GLS
At 7 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 2016 model has the highest pass rate at 93%.
Alternatives to the 2017 MERCEDES GLS
The MERCEDES GLS 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 (-2%) from 41,000 tests
- MERCEDES GLC (2018) 91% pass rate (-1%) from 40,494 tests
- AUDI A5 (2017) 89% pass rate (-3%) from 33,531 tests
- FORD RANGER (2019) 87% pass rate (-5%) from 32,194 tests