MOT defects · Engine, exhaust and leaks

Gearbox oil leak MOT advisory: what it means and which cars get it

In DVSA MOT data for 2023, analysed by RegTail, testers recorded this as an advisory on at least 0.2 in 100 initial MOT tests. The Land Rover Defender got it most often: recorded 5.1 times per 100 of its 112,814 tests.

DVSA wording: Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users.

Advisories

0.2 in 100

At least 52,068 tests in 2023

Most often

Land Rover Defender

5.1 per 100 tests

What it means

Oil is escaping from the gearbox, transfer box or differential, usually from a seal or gasket. As an advisory the tester has seen a leak that is not excessive.

How serious it is

A major defect, so a fail, when fluid is leaking excessively. The manual's guide is a pool more than 75mm across within 5 minutes.

Source: MOT inspection manual for cars and light vans, section 8.4.1.

Major Fail
It may affect the vehicle's safety, put other road users at risk or have an impact on the environment. Repair it immediately.
Advisory Pass
It could become more serious in the future. Monitor and repair it if necessary.

What fixing it usually involves

New seals or gaskets; drive shaft and output seals are common. Top up the oil if the level is low.

A general guide, not a quote: ask a garage to inspect the car.

Which models get it most

Per 100 initial MOT tests on each model, among the 25 models with at least 20,000 tests where it is among the 40 most common items. DVSA MOT data for 2023, analysed by RegTail.

Model	Tests	Advisory
Land Rover Defender	112,814	5.1
Suzuki Grand Vitara	24,508	3.4
Fiat Punto	72,390	2.8
Alfa Romeo Mito	20,894	2.5
Suzuki Jimny	25,207	2.5
Ford Fusion	58,809	2.0
Iveco Daily	38,031	1.9
Land Rover Freelander	130,402	1.8
Mercedes-Benz SLK	59,720	1.6
Jaguar XJ	25,292	1.6

What to check at a viewing

On the car
Look under the gearbox, and where the drive shafts leave it, for wet oil. Check gear changes are smooth on the test drive.
In the MOT history
If this appears as an advisory, see whether it came back at the next test or turned into a failure, and ask the seller for the receipt if it was fixed.

Check a specific car

Fleet averages only go so far. Enter the registration to see that car's own MOT history, mileage record and current condition, free.

Questions

What does "Gearbox oil leak" mean on an MOT?

Oil is escaping from the gearbox, transfer box or differential, usually from a seal or gasket. As an advisory the tester has seen a leak that is not excessive.

Gearbox oil leak: is it an MOT fail?

A major defect, so a fail, when fluid is leaking excessively. The manual's guide is a pool more than 75mm across within 5 minutes.

Which cars are most likely to get "gearbox oil leak" on an MOT?

In DVSA MOT data for 2023, analysed by RegTail, the models that got it most often were the Land Rover Defender (5.1 per 100 tests), the Suzuki Grand Vitara (3.4 per 100 tests), the Fiat Punto (2.8 per 100 tests).

More engine, exhaust and leaks defects

See every MOT defect we explain or MOT pass rates by model.

Oil leak Gearbox oil leak Exhaust leak Engine warning light on Lambda reading out of limits Airbag warning light on

How these figures are made. We counted the defects recorded at every initial MOT test (not retests) of cars and light vans in Great Britain in 2023 in the DVSA anonymised MOT dataset, 33,842,940 tests in all. Each item counts once per test. A failure is a major or dangerous defect, including one fixed during the test. A model's rate is the share of its tests where the item was recorded.

For each model we keep its 40 most frequent items, so a model where a defect is rarer than that is not listed, and figures for all cars are a floor. Defect names and explanations are ours, checked against the MOT inspection manual; DVSA's own wording is shown under each name.

Contains public sector information licensed under the Open Government Licence v3.0. RegTail's analysis of the DVSA anonymised MOT dataset, 2023 tests.