2018 · 6 years old at test · Diesel mostly

2018 Mercedes-Benz GLS MOT pass rate and common faults

524 MOT tests in 2024. 84.5% passed first time, compared with 82.5% for all cars the same age.

102Above average
Passed first time84.5%
Failed or needed repairs15.5%
Typical mileage at test51,000

Most common reasons for failing

Share of all 524 tests where this item caused a failure.

  1. Tyres - condition: has a cut in excess of the requirements deep enough to reach the ply or cords2.7%
  2. Joints: constant velocity boot split or insecure, no longer prevents the ingress of dirt2.3%
  3. Tyres - condition: has ply or cords exposed2.1%
    13 marked dangerous
  4. Tread depth below requirements of 1.6mm1.7%
    16 marked dangerous
  5. Registration plates: does not conform to the specified requirements1.1%
  6. Brake pads: less than 1.5 mm thick1.1%
    15 marked dangerous
  7. Tyres - condition: has a bulge, caused by separation or partial failure of its structure0.8%
    4 marked dangerous
  8. Brake pads: worn down to wear indicator0.8%
  9. Malfunction indicator lamp: inoperative or indicates a malfunction0.6%
  10. Tyres - condition: has ply or cords damaged0.6%
    4 marked dangerous

Problem areas

Failure items found per 100 tests, by part of the car.

  1. Tyres9.7%
  2. Brakes3.6%
  3. Body & chassis2.7%
  4. Number plates & VIN1.1%
  5. Lights & electrics1.1%
  6. Suspension0.8%
  7. Visibility (wipers, screen, mirrors)0.8%
  8. Emissions & leaks0.6%

Most common advisories

Not failures yet, but things the tester warned about.

  1. Tread depth below requirements of 1.6mm16.2%
  2. Brake pads: less than 1.5 mm thick5.3%
  3. Brake discs: in such a condition that it is seriously weakened3.8%
  4. Brake discs: significantly and obviously worn3.4%
  5. Non-component advisories: Child Seat fitted not allowing full inspection of adult belt2.7%

What this means if you are buying one

This model year does better than most cars its age, so it is a reasonable used buy on MOT record alone. Before buying, check the area that fails most: tyres - condition: has a cut in excess of the requirements deep enough to reach the ply or cords. Then look up the car's own MOT history on GOV.UK with its number plate, and look for repeat advisories.

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Questions

What is the MOT pass rate for a 2018 Mercedes-Benz GLS?

In 2024, 84.5% of 2018 Mercedes-Benz GLS cars passed their MOT first time, across 524 tests. The average for all 6-year-old cars was 82.5%.

What are the most common MOT failures on a 2018 Mercedes-Benz GLS?

The most common failure reasons were tyres - condition: has a cut in excess of the requirements deep enough to reach the ply or cords; joints: constant velocity boot split or insecure, no longer prevents the ingress of dirt; tyres - condition: has ply or cords exposed. The biggest problem area was tyres.

Is the 2018 Mercedes-Benz GLS reliable at MOT time?

Its MOT Rank score is 102, which is above average for a car of its age (100 means exactly average).