How reliable is the Mercedes-Benz G-Class compared with other cars?

We do not publish a comparison for the Mercedes-Benz G-Class, because the cars of this model that have been tested do not cover a wide enough range of ages and mileages. Its raw pass rate is 87.3% across 3,477 tests, but comparing a raw rate between models mostly ranks them by how new they are rather than how good they are. The failure and advisory patterns further down the page are still drawn from real tests and are worth reading.

What is the most common MOT failure on a Mercedes-Benz G-Class?

The item recorded most often is "A tyre seriously damaged", which appears in 21.0% of failed Mercedes-Benz G-Class tests. Because one failed test can list several items, these shares do not add up to 100%.

What do testers most often warn about on a Mercedes-Benz G-Class?

The most common advisory is "Tyre tread depth not in accordance with the requirements", noted on 11.3% of all Mercedes-Benz G-Class tests. An advisory is not a failure: it flags something that will likely need attention before the next test.

What mileage does a Mercedes-Benz G-Class usually have at its MOT?

The average odometer reading recorded at test is 46,542 miles. This is the mileage across all tested examples of every age, not an annual figure, so treat it as a description of the fleet rather than a target for one car.

Which Mercedes-Benz G-Class years are the most reliable?

Going by MOT pass rate, Mercedes-Benz G-Class cars first registered 2020–2022 do best at 92.0%, and those registered 2010 and earlier do worst at 71.3%. But that ordering is mostly age, not build year: almost every model passes less often as it wears, so the newest cars top this list whatever they are. A specific year looking strong here means little on its own; the failure items above, and the individual car's own MOT history, tell you far more.

Does a Mercedes-Benz G-Class get harder to pass as it ages?

Yes. At 3 to 5 years old, 92.0% of Mercedes-Benz G-Class tests pass. By fifteen years or more, that falls to 71.3%. Nearly every model follows this pattern, which is why comparing raw pass rates between models is misleading unless age is accounted for.

Are most Mercedes-Benz G-Class models petrol or diesel?

Of the Mercedes-Benz G-Class cars tested, 61% are petrol, 39% are diesel. Fuel type affects which items tend to fail, particularly emissions and exhaust components.

Model reliability file

Mercedes-Benz G-Class MOT pass rate & common failures

From 3,477 recorded MOT tests of the Mercedes-Benz G-Class, published by DVSA.

Data updated 29 July 2026

Quick answer

Across 3,477 MOT tests, 87.3% of Mercedes-Benz G-Class tests ended in a pass. This figure is not adjusted for age or mileage, so it is not a reliability ranking: the Mercedes-Benz G-Class fleet does not yet cover a wide enough spread of ages and distances to compare it fairly against other models. Its most commonly recorded failure is tyre seriously damaged, which appears in 21.0% of failed tests. Cars of this model average 46,542 miles on the odometer when tested.

At a glance

Recorded pass rate

87.3%unadjusted, not comparable3,477 tests

We are not publishing a ranking for the G-Class. The examples tested do not cover a wide enough spread of ages and mileages to compare it fairly, and an unadjusted pass rate mostly sorts models by how recently they were bought rather than how well they were built. The failure and advisory patterns below come from the same 3,477 tests and are worth reading on their own terms.

DVSA recorded wording

Most common failure items

Share of failed Mercedes-Benz G-Class tests in which each item was recorded. One failed test often lists several items, so these do not sum to 100%.

1.A tyre seriously damaged21.0%
78 occurrencesTyre damaged or deteriorated explained
2.Number plate does not conform to the specified requirements12.1%
45 occurrencesRegistration plate missing, insecure or illegible explained
3.A spring or spring component fractured or seriously weakened9.7%
36 occurrencesRoad spring broken or fractured explained
4.A brake lining or pad worn below 1.5mm9.4%
35 occurrencesBrake drum or shoe worn or contaminated explained
5.Tyre tread depth not in accordance with the requirements7.3%
27 occurrencesTyre worn close to the legal limit explained
6.Wiper blade missing or obviously not clearing the windscreen7.3%
27 occurrencesWiper or washer not working properly explained
7.A tyre cords visible or damaged5.6%
21 occurrencesTyre ply or cord exposed, or the casing separating explained
8.A lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning5.4%
20 occurrencesLamp not working explained
9.The aim of a headlamp is not within limits laid down in the requirements4.3%
16 occurrencesHeadlamp aim incorrect explained
10.Engine MIL illuminated indicating a malfunction4.0%
15 occurrencesEngine management light on, or not working explained

Warnings without a failure

Most common advisories

Share of all Mercedes-Benz G-Class tests carrying each advisory. The denominator differs from the failure list above because an advisory can be issued on a car that passed.

1.Tyre tread depth not in accordance with the requirements11.3%
391 testsTyre worn close to the legal limit explained
2.A tyre seriously damaged6.7%
231 testsTyre damaged or deteriorated explained
3.A brake lining or pad worn below 1.5mm6.0%
207 testsBrake drum or shoe worn or contaminated explained
4.Brake disc or drum excessively weakened, insecure or fractured5.0%
175 testsBrake disc worn, pitted or scored explained
5.Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users3.3%
114 tests
6.A shock absorber bush excessively worn2.4%
82 testsShock absorber defective explained
7.A tyre seriously damaged2.2%
76 testsTyre damaged or deteriorated explained
8.Brake disc or drum significantly and obviously worn2.0%
70 testsBrake disc worn, pitted or scored explained

The rest of the record

Everything else recorded on the Mercedes-Benz G-Class

The 18 other defects testers recorded on this model, beyond the most common listed above. Each links to what it means and what it takes to put right.

How wear changes the picture

G-Class pass rate by age and registration year

How often the Mercedes-Benz G-Class passes at each age, with the years those cars were first registered. Tests are from 2025, so a car aged 3 to 5 was first used in 2020–2022.

3–5 yrsreg. 2020–202292%

6–8 yrsreg. 2017–201988%

9–11 yrsreg. 2014–201682%

12–14 yrsreg. 2011–201383%

15+ yrsreg. 2010 and earlier71%

Read this as an age curve rather than a verdict on particular model years. Nearly every car passes less often as it gets older, so a newer G-Class outscoring an older one says more about wear than about how that year’s cars were built. Bands holding too few tests to be meaningful are omitted rather than shown as a rate.

What gets tested

The G-Class fleet

Average mileage recorded at test: 46,542
Fuel mix of tested cars: Petrol60.8%
Diesel39.1%

Trim names grouped into this model (13)

Recorded exactly as DVSA holds them. Trim-level names are rolled up so one model is not split across a dozen thin pages.

G 300
G 320
G 350
G 350 TURBO
G 400
G 400 AMG LINE PREM + D 4M A
G 400 AMG LINE PREM D 4MATIC A
G 400 EDITION D 4MATIC AUTO
G 500
G 55
G 55 AMG
G 63
G 63 AMG

Check a specific Mercedes-Benz G-Class

A model average tells you the pattern. Its own MOT record tells you the car.

Compare within the range

Other Mercedes-Benz models

Mercedes-Benz A-Class — 73.3% adjusted
Mercedes-Benz C-Class — 77.0% adjusted
Mercedes-Benz E-Class — 78.5% adjusted
Mercedes-Benz GLA — 82.3% adjusted
Mercedes-Benz Vito — 71.0% adjusted
Mercedes-Benz GLC — 85.9% adjusted
All Mercedes-Benz models

Common questions

How reliable is the Mercedes-Benz G-Class compared with other cars?: We do not publish a comparison for the Mercedes-Benz G-Class, because the cars of this model that have been tested do not cover a wide enough range of ages and mileages. Its raw pass rate is 87.3% across 3,477 tests, but comparing a raw rate between models mostly ranks them by how new they are rather than how good they are. The failure and advisory patterns further down the page are still drawn from real tests and are worth reading.
What is the most common MOT failure on a Mercedes-Benz G-Class?: The item recorded most often is "A tyre seriously damaged", which appears in 21.0% of failed Mercedes-Benz G-Class tests. Because one failed test can list several items, these shares do not add up to 100%.
What do testers most often warn about on a Mercedes-Benz G-Class?: The most common advisory is "Tyre tread depth not in accordance with the requirements", noted on 11.3% of all Mercedes-Benz G-Class tests. An advisory is not a failure: it flags something that will likely need attention before the next test.
What mileage does a Mercedes-Benz G-Class usually have at its MOT?: The average odometer reading recorded at test is 46,542 miles. This is the mileage across all tested examples of every age, not an annual figure, so treat it as a description of the fleet rather than a target for one car.
Which Mercedes-Benz G-Class years are the most reliable?: Going by MOT pass rate, Mercedes-Benz G-Class cars first registered 2020–2022 do best at 92.0%, and those registered 2010 and earlier do worst at 71.3%. But that ordering is mostly age, not build year: almost every model passes less often as it wears, so the newest cars top this list whatever they are. A specific year looking strong here means little on its own; the failure items above, and the individual car's own MOT history, tell you far more.
Does a Mercedes-Benz G-Class get harder to pass as it ages?: Yes. At 3 to 5 years old, 92.0% of Mercedes-Benz G-Class tests pass. By fifteen years or more, that falls to 71.3%. Nearly every model follows this pattern, which is why comparing raw pass rates between models is misleading unless age is accounted for.
Are most Mercedes-Benz G-Class models petrol or diesel?: Of the Mercedes-Benz G-Class cars tested, 61% are petrol, 39% are diesel. Fuel type affects which items tend to fail, particularly emissions and exhaust components.

How this was worked out

Method and limits

Figures come from the DVSA anonymised MOT testing dataset, published under the Open Government Licence. Only class 4 initial tests are counted: retests are excluded so a car appears once, and abandoned tests are excluded entirely. No adjusted rate is shown because this model's tested examples do not cover enough of the national age and mileage range for standardisation to mean anything.

An MOT measures whether a car met a legal standard on the day. It is not a breakdown record, a service history or a running-cost estimate, and a pass rate is a property of a fleet rather than a prediction about one car.